A Chat With Dr. Linda Perry - Archaeobotanist (www.fossilfarm.org)

[DonRocks]

Starting next Monday, we are privileged to host Dr. Linda Perry, one of the world's leading experts in the incredibly important, yet arcane, field of Archaeobotany, e.g., what were Aztecs granted as their last meal before being offered up as a midnight snack to Huitzilopochtli? Did Nicolas Cage really enjoy a honeybun before his demise in "The Wicker Man?" No, seriously ...

Dr. Perry is a Fulbright Senior Specialist in Archaeobotany, the study of the relationships between plants and our ancestors. She is a former Smithsonian Fellow, Research Collaborator, and Research Associate, and has been working with archaeobotanical samples for more than fifteen years. She holds degrees in biology, botany, and anthropology (!), and has been teaching in the fields of biology, botany, environmental science, archaeology, and anthropology for more than twenty years.

Linda's work incorporates archaeobotanical analyses into ancient contexts to gain insight into the behavior, organization, and development of past societies. To study these subjects, she employs many methods including microfossil analyses of microscopic residual remains of plants extracted from both artifacts and sediments, macro botanical analysis of larger fragments of plant remains, and wood identification.

Apart from ongoing research projects in the U.S. and China, Linda's current focus is the Foundation for Archaeobotanical Research in Microfossils, a 501©(3) organization she founded with the long-term goal of creating a dedicated space where archaeobotanical researchers can access state-of-the-art equipment, engage in peer consultation, and seek formal training (www.fossilfarm.org).

Our first question will be coming from José Andrés.

Okay, I'm teasing, *but* I am very proud to say that Linda is one of the main cogs of donrockwell.com: she is our Calendar Girl, singlehandedly responsible for recording all of DC's important restaurant and food events into our outstanding calendar. Do you see now why the calendar is so good? We have a genius running the damned thing. (Members, while you're thinking about it, before you read any further, please take a moment to record your birthday in your profile so it, too, will be in our calendar - if you don't do it now, you never will.)

Our members are scary-smart, and Linda is one of the scariest and smartest. Please feel free to begin with any questions you'd like, no matter how crazy or obscure you think they are. I'll start by asking Linda a couple questions. First, a softball: does Archaeobotany have accents on syllables 1 and 4, or 2 and 4? I'm guessing the former, as in archaeological. Now, what, exactly, do you do during a typical day? Do you stare at microscope slides of fecal matter preserved in amber, trying to figure out the dietary habits of obscure hominids? (I tagged this thread as I did for a reason.) Feel free to mention something from your Research Interests on your CV (*), if that's where your passion fruits. I'm sorry.

Could you give us a couple real-life examples of things that you've recently been working on, so we laypeople can get a solid, mental grasp of this difficult-to-understand line of work?

And thank you in advance for being with us (and thank you endlessly for doing such an amazing job on the calendar).

I really think this is going to be one of our most valuable chats. I have no idea whether or not it will be immediately popular, but I couldn't care less - it's important, and it's going to have a permanent home here where it will be lovingly curated until the ends of time.

(*) PS - I once got hammered at Gatsby's at SIU-Carbondale.

[zoramargolis]

Cool!

Linda-- could you comment on the "Grain Brain" hypothesis that has become so popular in the fad diet world? My peripheral attention to this has led me to be somewhat vague on the particulars, but it seems to have something to do with the wheat that is being grown for most commercial applications being very different from the grain eaten by our ancestors, and it being harmful to the human brain, leading to an increase in dementias. I could be way off, but as i said, I haven't focused much attention on the subject, but I have noticed that the book's author is getting a lot of buzz.

[Tweaked]

Did beer really save the world? But seriously has your research examined early alcohol use?

[lperry]

Good morning, and thank you, Don, for this opportunity.  I hope I can live up to a fraction of that introduction.

 First, a softball: does Archaeobotany have accents on syllables 1 and 4, or 2 and 4? I'm guessing the former, as in archaeological. Now, what, exactly, do you do during a typical day? Do you stare at microscope slides of fecal matter preserved in amber, trying to figure out the dietary habits of obscure hominids?

1 and 4.

A typical day starts at home where I caffeinate myself, try to wake up, and answer emails until the traffic has cleared off my route.  Then I head in to the lab.  If I have samples to study, they are almost always residues that I extract from artifacts, groundstone and flaked tools or ceramic sherds, or sediment samples, bags of dirt collected from various contexts that may be related to plant use.  I try to make the most of lab time by scanning slides on the microscope while the next set of samples is processing on the bench top.  By its nature, microscope work is time-limited.  Eye fatigue can come on quickly while scanning in search of tiny objects, so I don't do more than six samples in any one sitting.  Missing something after spending all the time and effort to extract the data would be a terrible loss.  Right now I'm working on samples from an Archaic site in central Texas, and many of the artifacts are burned rocks from cooking hearths and discard features.

For the past few months we have been hosting a doctoral student who is finishing up her dissertation research, so the lab is running all day and sometimes into the night.  It's very rewarding to me to have the space and equipment available to help others complete their work.

Most of the sites I've worked in the past few years are yielding plant remains with which I am familiar, but there are a few unknowns that I am still trying to identify.  It is this problem-solving / puzzle aspect of the work that I find most rewarding, and if I'm not working on archaeobotanical samples, I'll study modern comparative materials.  I have visions of an online database in which researchers can plug in their data and images for everyone to share, but I have no idea if something like that is possible to create.    

I spend a fair amount of time compiling data and writing up findings for presentations or publications.  I am less disciplined with this part of the process than I would like to be, and I usually write when I am in the mood to do so rather than on a regular schedule as I should.  I also spend time reading journals and books, and also reviewing articles and grant proposals.  Peer-review is an important part of the process, and I put in time and effort with the hope that others will be as thoughtful with my manuscripts.

I serve on a couple of boards and committees, so I spend a few days a month in the District.  Today and tomorrow are such days, so I will try to anwer questions in the evenings when I am back home and significantly more awake.

Could you give us a couple real-life examples of things that you've recently been working on, so we laypeople can get a solid, mental grasp of this difficult-to-understand line of work?

Do you really think it is difficult to understand?  I hope not.  I think that it is more likely that the proliferation of misinformation in the media and the popularity of Indiana Jones movies have given people the wrong impression about what archaeologists do.  Archaeology is very detail-oriented and involves a great deal of careful and meticulous observation, note taking, measuring, comparing, cataloging, etc.  A friend of mine used to say that I spend my days washing dirty dishes and checking out what people left on their plates.  It just happens that the dishes are hundreds or thousands of years old, and the fragments of materials from the plates are so small that I need a microscope to understand what they are.  Sounds really glamorous, right? 

[lperry]

Cool!

Linda-- could you comment on the "Grain Brain" hypothesis that has become so popular in the fad diet world? My peripheral attention to this has led me to be somewhat vague on the particulars, but it seems to have something to do with the wheat that is being grown for most commercial applications being very different from the grain eaten by our ancestors, and it being harmful to the human brain, leading to an increase in dementias. I could be way off, but as i said, I haven't focused much attention on the subject, but I have noticed that the book's author is getting a lot of buzz.

I haven't heard of the "Grain Brain."  I have heard people claim that our modern crops are different from ancient ones, and selection has undoubtedly changed crops over the years, but we don't have nutritional analyses of archaeological specimens, so it is unclear to me how they can make a one-to-one comparison with any validity.

It is also worth noting that microevolutionary trends in human groups since the Neolithic revolution are well documented - adaptations like lactose digestion in adults in pastoralist societies or the ability to ingest cyanogenic compounds from manioc tubers without nerve damage in South American indigenous groups.  So people have changed along with the changes in diet.

When people ask me about living like our ancestors did, I tell them that there is only one thing that is common across the planet in all ancestral groups, and that is exercise.  If you want to live like our ancestors did, move more.

[lperry]

Did beer really save the world? But seriously has your research examined early alcohol use?

I don't know about saved, but it certainly changed the world.     The manipulation of yeast for fermentation purposes allowed humans to create a number of nutritionally superior foods including bread.

I studied breweries at Hierakonpolis, a pre-dynastic site in Upper Egypt, but the results are not yet published, so I can't go into detail (sorry.)  There is a group of archaeologists who focus on ancient alcohol production, and they hold regular meetings.  I'll see if I can remember their name or find a website for you.

[jayandstacey]

Cool - so many questions!

- What are the 2 or 3 most important unanswered questions in your field right now?  The questions who's answers would have the greatest impact on our understanding of the world?

- How is a perfect specimen delivered?  Via amber?  Glacial ice?  Ash?  Locked in arid sandstone?

- I imagine a kind of evolutionary tree of plants/foods.  It has thousands, maybe millions of branches, many of which died off at some point.  I assume we only know a small % of those branches, and that as we go back in time the picture gets cloudier, despite the diversity decreasing (going back down the evolutionary tree....)   So...

       - How do you identify a specimen back onto that tree?  Are you studying cell structure, or DNA, or something else?  - or aren't you going that far back in time (ie, maybe you're only working in the last 6000 years; an eye blink in the evolution of plants...(right?) )

       - Is a part of your work to identify new (to us) plants and foods?  Or does that not come up much?

       - Do you work with other scientists to extrapolate understanding, for instance, someone else working in a location was able to determine the time frame (say, 10,000 BC) and you then work from that info?

- And maybe the simplest question - I *think* you focus on plants that have intertwined with humans - as food or maybe building materials or tools.  How do you know that this has happened?  I mean, all humans have plants growing all around us - and if my house rolled under a Pompeii-ish ash dump tomorrow, you'd find garden plants, weeds, semi-wild plants, house plants, uncooked food plants, cooked food plants, etc.  Is part of your job essentially to sort through all those to provide deeper historical insight?

[jayandstacey]

Oh - and one more - the fourth grader in me wants to know what got you into this field. (well, so does the adult )

[DonRocks]

Do you really think it is difficult to understand?  I hope not.  I think that it is more likely that the proliferation of misinformation in the media and the popularity of Indiana Jones movies have given people the wrong impression about what archaeologists do.  Archaeology is very detail-oriented and involves a great deal of careful and meticulous observation, note taking, measuring, comparing, cataloging, etc.  A friend of mine used to say that I spend my days washing dirty dishes and checking out what people left on their plates.  It just happens that the dishes are hundreds or thousands of years old, and the fragments of materials from the plates are so small that I need a microscope to understand what they are.  Sounds really glamorous, right? 

No, it's not necessarily difficult to understand; it's just something whose methods people aren't aware of.

I once read a book on history, written from a paleontological viewpoint, at the precise level where people like me (the "PBS crowd," the "intelligent laymen," the "dilettantes") would get a lot out of. It's called "Life: A Natural History Of The First Four Billion Years Of Life On Earth" by Richard Fortey, who, along with being a senior paleontologist at London's Natural History Museum, is quite a character - sort of "Indiana Jones" old-school (readers can peak inside the book on Amazon and see if it would interest them - I remember enjoying it very much while being moderately challenged). The book ends where civilization starts, so it would be of no interest to you. Anyway, it has been a good ten years since I've read it (it's sitting next to me right now because books that I take weeks, months, or sometimes years to finish are never, ever discarded), and there are exactly three words that I still remember to this day because of their elegant simplicity: "Bones don't lie."

While that neat little phrase may be true, I also wonder in your case, if "bones" can ask more questions than they answer. I suppose that bones neither ask nor answer questions; they're merely data to be analyzed - pieces of the puzzle, so to speak.

[lion]

Do you have any thoughts on the recent discovery of tobacco ringspot virus jump from plants to honeybees?

Thanks for doing the chat!

[lperry]

Wow!  Please bear with me - it may take a while to answer all of these. 

- What are the 2 or 3 most important unanswered questions in your field right now?  The questions who's answers would have the greatest impact on our understanding of the world?

I'm going to try to answer this question with a story.  A few years ago, I was at an airport in a coach that was heading out to the plane, and someone noticed the book of abstracts I was reading and asked me about the archaeology convention I had just attended.  The gentleman got very animated, told me how he was fascinated by archaeology, and asked me "what was the one, amazing find everyone was talking about?"  He was looking at me with a combination of anticipation and glee.  I carefully explained that there had been more than 5000 archaeologists at the meetings, with hundreds of symposia covering different geographic areas, time periods, cultures, and categories of data.  We all have a general knowledge base, however, like people in most fields, we tend to stick to our areas of specialization, and different questions are important in different contexts.  What might be important to the person working on Neolithic landscape modification in Papua New Guinea may not resonate with someone who studies Archaic lithic technology in Idaho.  In short, it doesn't really work that way.  He looked taken aback, and really disappointed.  "Oh."  So there it is.  It doesn't really work that way, and I feel like I can never answer questions like this one without disappointing people, at least a little, and having them think, "oh."    

That said, what I do think is important in my field right now is a trend toward the combination of multiple lines of evidence, such as the study of macroremains, phytoliths, and starch grains from the same contexts, thus providing a more complete picture of plant use in a given site.  Different plants will occur in the record in different forms, so the best way to find everything we can is to look at the same contexts using a battery of methods.  The other issue that concerns me is the loss of lab space as people retire and are not replaced due to budgetary constraints.  An archaeobotanist used to be able to work with a compound dissecting microscope, a probe, and a desk.  Now some of us need fume hoods, ultrasonic cleaners, centrifuges, and compound light microscopes.  Lab space and equipment is not traditionally included in Anthropology or Archaeology departments, but the work is in great demand.  I am doing my best to address both of these issues in the work that I do.

[lperry]

- How is a perfect specimen delivered?  Via amber?  Glacial ice?  Ash?  Locked in arid sandstone?

If by "perfect" you mean most like what was originally deposited into the record by human activity, I would say it's a toss up between waterlogged and arid preservation.  Waterlogged sites, those flooded with water, allow for little to no microbial activity that might decompose the remains once the oxygen is depleted, and entire, intact specimens can be recovered.  In arid areas like coastal Peru, you can dig into a midden and pull out a corncob that looks pretty much like it did when someone discarded it a couple of thousand years ago.  The dry air desiccates specimens and, again, prevents microbial activity from degrading the remains.

The residue analyses I and others do are so useful because the conditions I described above are exceptionally rare.  Most sites are in the open, exposed to the elements, and microbes liked to eat what we threw away millennia ago just as much as they do today.  Think about what happens in your compost pile, then think about your compost pile after a few thousand years.

[lperry]

- I imagine a kind of evolutionary tree of plants/foods.  It has thousands, maybe millions of branches, many of which died off at some point.  I assume we only know a small % of those branches, and that as we go back in time the picture gets cloudier, despite the diversity decreasing (going back down the evolutionary tree....)   So...

       - How do you identify a specimen back onto that tree?  Are you studying cell structure, or DNA, or something else?  - or aren't you going that far back in time (ie, maybe you're only working in the last 6000 years; an eye blink in the evolution of plants...(right?) )

       - Is a part of your work to identify new (to us) plants and foods?  Or does that not come up much?

       - Do you work with other scientists to extrapolate understanding, for instance, someone else working in a location was able to determine the time frame (say, 10,000 BC) and you then work from that info?

The tree of plant use by humans, which is what I study, is more of an upside-down one, with lots of branches at the bottom that then fall away as we move to the present.  Humans and our ancestors around the world have exploited an estimated 30,000 plant species for food in the past, and about 30 feed us today.  So, yes, we frequently don't know what we might be looking for, because it isn't important to us today.  That doesn't mean, however, that it isn't still in the environment in a different form.  As an example, ancient indigenous people in the Mississippi River valley domesticated and grew crops called sumpweed, canarygrass, and goosefoot.  These plants still occur in the flora, but it's not like you find them in the grains aisle at Harris Teeter.  Goosefoot, interestingly, is Chenopodium berlandieri, a relative of Chenopodium quinoa, the "superfood" quinoa of the Andes.  We have our own, North American superfood domesticated by Native Americans.  Why isn't someone marketing this?

To identify plants, we use a one-to-one comparison with modern plant specimens.  Even 100,000 years is the blink of an eye in plant evolution, and when we look at domesticated plants that occurred more recently, we frequently know the wild progenitors, so we can study those as well.  If there are large fragments of plants or seeds, you can use gross morphology.  A quinoa seed from Costco looks pretty much like one from an ancient Andean context.  Microfossils are ultrastructural components of plant cells, so we can use light microscopy or SEM, for example, for comparative purposes.  Just like larger structures in plants like flowers or leaves are distinctive, tiny fragments can also be diagnostic of certain taxa.  So starch grains from those Costco quinoa seeds can be compared to starch grains extracted from a ceramic sherd from a cooking pot, for example.  There are people who work with ancient DNA, but I am not one of them.  There are also people who work with lipid and other chemical residues.    

New plant foods come up sometimes, but not frequently in my work, at least so far.

I'm not sure what you are asking in the last part of the question.  If you are asking how dating is completed, in some areas that are extremely well studied, the patterns on a ceramic sherd can tell the researcher how old the site is.  In other areas, we use radiocarbon dating of charred materials, and there are several laboratories that specialze in radiocarbon dating.  I am frequently asked to identify wood charcoal specimens prior to sending them to the lab for dating, as the process is destructive.  I adore wood identification.  You have to view the specimen in three different planes of view and puzzle out anatomical features of different cell types and configurations.  It's fairly easy in temperate regions, but tropical woods have tiny cells and thousands of variants.  (See?  You really don't want to be an archaeologist after all. )

[lperry]

I have to sign off for tonight, but will be back online tomorrow morning to finish up these posts.  Please keep the questions coming!

[DonRocks]

I have to sign off for tonight, but will be back online tomorrow morning to finish up these posts.  Please keep the questions coming!

Linda!

Pace yourself!

Nobody is expecting you to field every question in a day or for that matter even a week!

(Thank you for doing this so far.)

[lperry]

Linda!

Pace yourself!

Nobody is expecting you to field every question in a day or for that matter even a week!

(Thank you for doing this so far.)

Will do.

[jayandstacey]

I'm going to try to answer this question with a story.  A few years ago, I was at an airport in a coach that was heading out to the plane, and someone noticed the book of abstracts I was reading and asked me about the archaeology convention I had just attended.  The gentleman got very animated, told me how he was fascinated by archaeology, and asked me "what was the one, amazing find everyone was talking about?"  He was looking at me with a combination of anticipation and glee.  I carefully explained that there had been more than 5000 archaeologists at the meetings, with hundreds of symposia covering different geographic areas, time periods, cultures, and categories of data.  We all have a general knowledge base, however, like people in most fields, we tend to stick to our areas of specialization, and different questions are important in different contexts.  What might be important to the person working on Neolithic landscape modification in Papua New Guinea may not resonate with someone who studies Archaic lithic technology in Idaho.  In short, it doesn't really work that way.  He looked taken aback, and really disappointed.  "Oh."  So there it is.  It doesn't really work that way, and I feel like I can never answer questions like this one without disappointing people, at least a little, and having them think, "oh."

I remember that flight!

(just kidding)

Yeah, in this Olympics/Superbowl/Holy Grail world we tend to think of everything having a "peak" that everyone else strives for.

I keep talking to my 12 year old daughter about her path to the top ranks of the equestrian world. "Dad, I just want to ride and compete and have fun with my friends."  

That said, what I do think is important in my field right now is a trend toward the combination of multiple lines of evidence, such as the study of macroremains, phytoliths, and starch grains from the same contexts, thus providing a more complete picture of plant use in a given site.  Different plants will occur in the record in different forms, so the best way to find everything we can is to look at the same contexts using a battery of methods.  The other issue that concerns me is the loss of lab space as people retire and are not replaced due to budgetary constraints.  An archaeobotanist used to be able to work with a compound dissecting microscope, a probe, and a desk.  Now some of us need fume hoods, ultrasonic cleaners, centrifuges, and compound light microscopes.  Lab space and equipment is not traditionally included in Anthropology or Archaeology departments, but the work is in great demand.  I am doing my best to address both of these issues in the work that I do.

Interesting. The multiple lines of evidence thing is where I was going in my next question...

[jayandstacey]

The tree of plant use by humans, which is what I study, is more of an upside-down one, with lots of branches at the bottom that then fall away as we move to the present.  Humans and our ancestors around the world have exploited an estimated 30,000 plant species for food in the past, and about 30 feed us today.  So, yes, we frequently don't know what we might be looking for, because it isn't important to us today.  That doesn't mean, however, that it isn't still in the environment in a different form.  As an example, ancient indigenous people in the Mississippi River valley domesticated and grew crops called sumpweed, canarygrass, and goosefoot.  These plants still occur in the flora, but it's not like you find them in the grains aisle at Harris Teeter.  Goosefoot, interestingly, is Chenopodium berlandieri, a relative of Chenopodium quinoa, the "superfood" quinoa of the Andes.  We have our own, North American superfood domesticated by Native Americans.  Why isn't someone marketing this?

Interesting and contrary to my assumption.

I can imagine a SuperBowl ad where a guy is tailgating and tosses a frozen Goosefoot patty onto the grill. "Goosefoot?!?! I ate one by accident last time and we won. It's good luck! But it tastes like a dirty old tree branch..."

To identify plants, we use a one-to-one comparison with modern plant specimens.  Even 100,000 years is the blink of an eye in plant evolution, and when we look at domesticated plants that occurred more recently, we frequently know the wild progenitors, so we can study those as well.  If there are large fragments of plants or seeds, you can use gross morphology.  A quinoa seed from Costco looks pretty much like one from an ancient Andean context.  Microfossils are ultrastructural components of plant cells, so we can use light microscopy or SEM, for example, for comparative purposes.  Just like larger structures in plants like flowers or leaves are distinctive, tiny fragments can also be diagnostic of certain taxa.  So starch grains from those Costco quinoa seeds can be compared to starch grains extracted from a ceramic sherd from a cooking pot, for example.  There are people who work with ancient DNA, but I am not one of them.  There are also people who work with lipid and other chemical residues.    

New plant foods come up sometimes, but not frequently in my work, at least so far.

I'm not sure what you are asking in the last part of the question.  If you are asking how dating is completed, in some areas that are extremely well studied, the patterns on a ceramic sherd can tell the researcher how old the site is.  In other areas, we use radiocarbon dating of charred materials, and there are several laboratories that specialze in radiocarbon dating.  I am frequently asked to identify wood charcoal specimens prior to sending them to the lab for dating, as the process is destructive.  I adore wood identification.  You have to view the specimen in three different planes of view and puzzle out anatomical features of different cell types and configurations.  It's fairly easy in temperate regions, but tropical woods have tiny cells and thousands of variants.  (See?  You really don't want to be an archaeologist after all. )

I was actually more curious about the interaction/coordination between yourself and other scientists that might be working on a particular site, or project or toward a particular goal. I literally didn't know if you worked completely in a vacuum and only shared through publishing, or created a team of different disciplines to work in a coordinated way on a particular problem, or somewhere in between. By answering the question you thought I asked, you answered the question I meant to ask

Thanks for answering my novice questions! When I first entered the "real world" workforce, it struck me how many intelligent people were around me. I decided early on that if there was at least one person in the room smarter than me...shame on me if I don't leave that room knowing at least one new thing. It is the one collection/currency where I can accumulate vast amounts yet never spend a dime doing so.

Thank you - very interesting.

[lperry]

- And maybe the simplest question - I *think* you focus on plants that have intertwined with humans - as food or maybe building materials or tools.  How do you know that this has happened?  I mean, all humans have plants growing all around us - and if my house rolled under a Pompeii-ish ash dump tomorrow, you'd find garden plants, weeds, semi-wild plants, house plants, uncooked food plants, cooked food plants, etc.  Is part of your job essentially to sort through all those to provide deeper historical insight?

Yes.  For example, unless we find something in stomach contents, dental calculus, or in coprolites, there is inference involved in defining "food", and we try to interpret the best we can using modern analogues.  I tend to think we are more likely to dismiss a food plant as a meaningless weed rather than categorize something as food that was unimportant, simply because we have narrowed our plant food resources so much over the years.  I could, however, be wrong about that.

Interpretation is why context is so important in archaeology; where something is located in the site gives us important information about how it was used and what it meant to the person or people who came into contact with it.  That's why the community tries to educate people about looting sites and collecting artifacts out of context.  We hope that collectors around the world come to an understanding that owning an object that might be beautiful is not as important as understanding our cultural heritage.

[DonRocks]

Interpretation is why context is so important in archaeology; where something is located in the site gives us important information about how it was used and what it meant to the person or people who came into contact with it.  That's why the community tries to educate people about looting sites and collecting artifacts out of context.  We hope that collectors around the world come to an understanding that owning an object that might be beautiful is not as important as understanding our cultural heritage.

Are there any plants (edible or otherwise) that were considered sacred in the cultures you're studying? If so, could you cite some examples, and also tell us how you know? Or do you not really care about any religious context, and instead concentrate exclusively on the nutritional/diet aspect of things?

If you could list your three greatest areas of expertise, in order from greatest to third-greatest, what would they be? (Three is obviously a number I picked rather haphazardly.) With so many different areas in this field, I'm still trying to get a grasp on your subspecialties.

[ol_ironstomach]

This is absolutely fascinating, and thanks to jayandstacey for asking a number of questions I was curious about, and a bunch of even better ones.

Apologies for the open-ended question, but in broad strokes, how much can currently be determined about the early history of food preparation methods from the evidence?  Beyond raw ingredients, do recognizable details suggest how raw materials were processed?  Mechanically altered?  Heated?  Cooked in complex ways?

Similarly, besides assumptions about available Calories from changes like the lactose tolerance mutation, or the introduction of potatoes, what sorts of ancient dietary shifts (if any) should be of blockbuster interest, beyond the customary grade school handwaving of "hunter-gatherers settled down"?

Also, other than Otzi the Iceman and I imagine some Siberian mammoths, are there any other stomach contents of interest from *really* ancient remains?

And finally, tossing in a Weekly World News question: what do you make of the recent attempt to identify the flora depicted in the controversial Voynich manuscript?

[lperry]

Oh - and one more - the fourth grader in me wants to know what got you into this field. (well, so does the adult )

Someone who knew me better than I knew myself got me into this field.  When I was in grad school at UF in the Botany department, one of my professors was on the dissertation committee of an archaeobotanist.  I remember him showing me the dissertation and saying, "you should do this.  This is you."  I'm pretty sure I gave him a look like he was mental, and the conversation went back and forth for a few minutes in that vein.  Long story short, a year or so later, I figured out that he was right.  So a big thank you to Jack Ewel for showing me the way.

[lperry]

No, it's not necessarily difficult to understand; it's just something whose methods people aren't aware of.

I once read a book on history, written from a paleontological viewpoint, at the precise level where people like me (the "PBS crowd," the "intelligent laymen," the "dilettantes") would get a lot out of. It's called "Life: A Natural History Of The First Four Billion Years Of Life On Earth" by Richard Fortey, who, along with being a senior paleontologist at London's Natural History Museum, is quite a character - sort of "Indiana Jones" old-school (readers can peak inside the book on Amazon and see if it would interest them - I remember enjoying it very much while being moderately challenged). The book ends where civilization starts, so it would be of no interest to you. Anyway, it has been a good ten years since I've read it (it's sitting next to me right now because books that I take weeks, months, or sometimes years to finish are never, ever discarded), and there are exactly three words that I still remember to this day because of their elegant simplicity: "Bones don't lie."

While that neat little phrase may be true, I also wonder in your case, if "bones" can ask more questions than they answer. I suppose that bones neither ask nor answer questions; they're merely data to be analyzed - pieces of the puzzle, so to speak.

Always be wary of elegant simplicity.   Data exists in the form we find it, but it is humans who analyze and interpret the data, and humans are messy creatures who view everything through a cultural lens.  If you put a newly discovered skeleton of an ancient hominid on a table in front of ten different physical anthropologists who are competing for a limited pool of grant money, you will undoubtedly get a few different interpretations of where these particular fossils fit in our evolutionary history, and where we should next look for the greatest chance of gaining the most knowledge.  Throw a creationist into the mix, and all bets are off.  The story those bones tells also changes as our science advances and we find out, for example, that we need to calibrate radiocarbon dates, or we learn how to extract DNA from them.  So, yes, those bones are pieces of the puzzle, but the picture that puzzle shows is always changing, and that change is what drives so many scientists.  We love looking for that next piece of the puzzle and figuring out where it fits into the picture.

Lion, I'm going to do a little reading today before I answer your question.  My Grandfather kept bees, and my cousin has them in her backyard and has been dealing with the mites.  I haven't read anything outside the popular press, and that's usually not the best source, so thanks, and I'll get back to you later.

As an edit to that comment, I just read the phrase "transkingdom host alteration."  I'm going to try to work that phrase into my daily vocabulary.

[lion]

Lion, I'm going to do a little reading today before I answer your question.  My Grandfather kept bees, and my cousin has them in her backyard and has been dealing with the mites.  I haven't read anything outside the popular press, and that's usually not the best source, so thanks, and I'll get back to you later.

As an edit to that comment, I just read the phrase "transkingdom host alteration."  I'm going to try to work that phrase into my daily vocabulary.

Thanks for taking the time. It was on a few sites recently and coming across it, I mentally flagged it as a point of interest. My reading was limited to the Scientific American article- http://blogs.scientificamerican.com/artful-amoeba/2014/01/31/suspicious-virus-makes-rare-cross-kingdom-leap-from-plants-to-honeybees/.

[lperry]

Thanks for taking the time. It was on a few sites recently and coming across it, I mentally flagged it as a point of interest. My reading was limited to the Scientific American article- http://blogs.scientificamerican.com/artful-amoeba/2014/01/31/suspicious-virus-makes-rare-cross-kingdom-leap-from-plants-to-honeybees/. 

Happy to do it.  It was on my list as well.

Here's a link to the actual article as published in mBio, a microbiology journal.  They are open access (kudos - they all should be), so you can click on a PDF link to the right of the abstract and have a look at what the scientists wrote.  It's significantly less sensational and alarmist than the press it got, but that's not unusual.

The press take seems to be that this is a freakish and unusual turn for a virus, and it happened just now, and it could wipe out all the bees, and then there will be no crops, and life as we know it will end, etc.  The article indicates they found the virus recently (in Beltsville bees - go DC Metro area), but it is not necessarily a recent development in honeybee/virus coevolution.  It could have happened some time ago, it is just now that the scientists figured out it was there, and it is a particularly interesting virus because it crossed from plant to animal.  The researchers hope that the understanding of the virus/bee relationship will help in both controlling the spread of this type of disease in agriculture and maintaining the health of bee hives over winter, when they tend to decline.

I think I just made this story significantly more boring for you.  Sorry about that.

[lperry]

Thanks for answering my novice questions! When I first entered the "real world" workforce, it struck me how many intelligent people were around me. I decided early on that if there was at least one person in the room smarter than me...shame on me if I don't leave that room knowing at least one new thing. It is the one collection/currency where I can accumulate vast amounts yet never spend a dime doing so.

Thanks for asking some really good questions, and I'm pretty sure your strategy makes you the smartest person in the room.

[lion]

Happy to do it.  It was on my list as well.

Here's a link to the actual article as published in mBio, a microbiology journal.  They are open access (kudos - they all should be), so you can click on a PDF link to the right of the abstract and have a look at what the scientists wrote.  It's significantly less sensational and alarmist than the press it got, but that's not unusual.

The press take seems to be that this is a freakish and unusual turn for a virus, and it happened just now, and it could wipe out all the bees, and then there will be no crops, and life as we know it will end, etc.  The article indicates they found the virus recently (in Beltsville bees - go DC Metro area), but it is not necessarily a recent development in honeybee/virus coevolution.  It could have happened some time ago, it is just now that the scientists figured out it was there, and it is a particularly interesting virus because it crossed from plant to animal.  The researchers hope that the understanding of the virus/bee relationship will help in both controlling the spread of this type of disease in agriculture and maintaining the health of bee hives over winter, when they tend to decline.

I think I just made this story significantly more boring for you.  Sorry about that.

Not at all, I find the news very interesting especially in regards to Colony Collapse Disorder. A lot of science occurs by accumulation of bits and pieces of data that hopefully, develops into advancement and knowledge.

In college I worked measuring Organochlorine pesticides and PCBs levels in the Chesapeake Bay tributaries and it was an arduous task to get 50 L water samples. But each distillation resulted in another a data point.

The plant to animal virus jump is interesting and appears to be an another found puzzle piece in CCD research.

Thanks for the reply!

[DonRocks]

Not at all, I find the news very interesting especially in regards to Colony Collapse Disorder. A lot of science occurs by accumulation of bits and pieces of data that hopefully, develops into advancement and knowledge. 

I get the impression that Linda can't believe her mundane, piecemeal job could possibly interest anyone; I also get the impression that a lot of people are glued to the computer, hanging on her every word.

Substance ... it's a beautiful thing.

[johnb]

Linda -  fascinating discussion.  Here's something I've always wondered about, which may be a bit tangental to the discussion so far, but I'll ask anyway.  I've always wondered how early humans found and got focused on the things that turned out to be useful or desirable for food, drugs, whatever.  Somewhere above I think you mentioned there have been perhaps 30,000 plants used as foods; yet there must be many times that which aren't useful to humans for food.  So the good ones had to be sorted out from a lot of contenders.  Obviously there must have been lots of trial and error, but how did they go about this trial and error process?  How did the process unfold?  How many things had to be tried to find the few that turned out to be useful, and how did ancient peoples measure which ones those were?  Surely there was more to it than just random natural selection!  In particular, how were things discovered where non-obvious processing is needed, like adding lime to corn, or fermentation of soybeans to make sauce (I know it happens naturally, but still....).

I'm reminded of that old phrase about he being brave the first man to try an oyster.

[lperry]

Are there any plants (edible or otherwise) that were considered sacred in the cultures you're studying? If so, could you cite some examples, and also tell us how you know? Or do you not really care about any religious context, and instead concentrate exclusively on the nutritional/diet aspect of things?

Ceremonial or religious contexts are very important in understanding cultures, but many times it can be difficult to understand what might have been important in a symbolic way.  Ancient cultures were different from ours, and because we use inference filtered through our own cultural biases, interpretation can be difficult if there is not some very clear representation or context, like a painting that shows people or gods using the plant, or a building with an altar where the plant was clearly an offering, or the plants are part of a burial and were sent with the dead to the afterlife.  There are archaeologists who work their entire careers with cultures in which ceremonial plant use is well understood due to writings or other representations.  I usually work with cultures that we know from some burned rocks, grinding tools, flaked lithic implements, maybe a midden deposit, and, if we get really lucky, remnants of a house like post molds.

Getting back to your specific question, I have recovered tobacco seeds from sites, and tobacco was important in the ritual lives of many indigenous groups in the Americas.  It was also, however, used for other purposes such as staving off hunger during lean times.  It works, too, which is probably why cigarettes are so prevalent in the modeling industry.  So again, context and interpretation are key.

As an aside, one of the most interesting books on the ritual use of plants I've read is Johannes Wilbert's Tobacco and Shamanism in South America.  I have met the author, but have no other affiliation.  Just a fascinating read if you happen to be looking for one.

[lperry]

I appreciate everyone asking thoughtful questions, and I also appreciate your patience as I take a little time to give each one some thought.  When I last did an online chat, it was with some middle school students, and my best question was, "what's the grossest thing you've ever found?"

[Barbara]

I appreciate everyone asking thoughtful questions, and I also appreciate your patience as I take a little time to give each one some thought.  When I last did an online chat, it was with some middle school students, and my best question was, "what's the grossest thing you've ever found?"

And, the answer was  . . .?

[jayandstacey]

And, the answer was  . . .?

Don Rockwell

[jayandstacey]

Do you have a more bounded specialty within your field, like expertise based on

- a certain geography

- a certain time period

- a certain group of associated researchers

- the whims of your funding source?

- or other, or not at all? (I suppose Archeobotany is fairly specialized to begin with)

Sliced another way, why would someone in need of Archeobotanist call you vs. another Archeobotanist?

[lperry]

If you could list your three greatest areas of expertise, in order from greatest to third-greatest, what would they be? (Three is obviously a number I picked rather haphazardly.) With so many different areas in this field, I'm still trying to get a grasp on your subspecialties.

I've never been asked this question.  #1 is easy, starch grain analysis, as I have spent the most time both implementing and teaching this type of work.  #2 and #3 are more difficult to decide, but I'll put wood identification next, followed by phytolith work.  I put the wood ID first because, although researchers who can perform this analysis are easier to come by in Europe, it is unusual to find a plant anatomy course any more in the US, much less wood anatomy.  I think the skill is more rare than phytolith analysis.  I began my studies in the field with macrobotanical analysis, and I do enjoy that work looking at fragments of charred seeds and fruits, but I am rarely asked to do it.  There are fewer people working with the starches, and they have become powerful tools for making the previously invisible visible in the archaeological record.

Edit:  I assumed you were asking about skill sets relevant to the work, not things like teaching, mentoring, problem solving, etc.

[lperry]

Apologies for the open-ended question, but in broad strokes, how much can currently be determined about the early history of food preparation methods from the evidence?  Beyond raw ingredients, do recognizable details suggest how raw materials were processed?  Mechanically altered?  Heated?  Cooked in complex ways?

Thanks for the question, and thanks for knowing it could take a library to answer it.  Here goes in broad strokes.

Context is (again) important in this type of analysis.  If we recover plant remains from the used edge of a slicing blade, or from the worn surface of a grinding stone, it's not a leap to infer that the plant foods were processed with these tools.  Different categories of plant remains, starches, phytoliths, or larger, charred pieces, can give us different types of information about processing.

Because most plant remains decompose over time, the record is fragmentary and biased by what does preserve.  Macroremains, larger fragments of plants or seeds, typically occur as charred remains; black carbon isn't particularly palatable to decomposers.  Charred remains are usually various bits and pieces of foods that were accidentally burned when they were over-cooked or were dropped into a fire, so specific methods can be difficult to assess.  We may be lucky if someone burned a whole pot of something, or had a big pit fire that didn't completely consume the contents, but those contexts are unusual.

Phytoliths are silica microfossils, and they will char and distort when burned, so heating in a fire is recognizable in the record, and I have also seen phytoliths that have been cut cleanly by lithic tools used to process grain.  The best information we have right now, however, is from starch grains.

With starch remains, we can figure out how plant foods were processed based upon distinctive damage to the semi-crystalline nature of the grain when it is baked, boiled, ground with stone tools, dry-parched, freeze-dried, etc.  There must be an understanding of the native state of the starch grain, how it comes out of the plant raw, which is then compared with various changes that occur with different types of processing.  We have some nice comparative studies that have been completed by archaeobotanists performing modern experiments with the same types of foods that we find in ancient contexts.  Researchers also do experiments on the fly, as it were, if they happen across a pattern in the record that they think might be identifiable.  I've ground up, sliced, pounded, and cooked a lot of roots, tubers, and seeds trying to replicate the damaged remains I have found in different sites.

We also have a vast library of literature from the food and industrial sciences where starches are studied for changing properties under all sorts of different conditions.  Starch is the powder in powdered latex gloves (which we don't use in our labs), it is used as a dry lubricant in industrial machinery, and it is also an important source of calories for humans.  That's three off the top of my head, but I just plugged "starch industry" into Google Scholar and got over 700,000 hits.  That's a whole lot of people making detailed studies of vast numbers of plant starches under all sorts of conditions, and an amazing amount of information we can use.  I know I have just scratched the surface in my own studies of these literatures.

I think chemical residue analyses may be the way of the future.  Why is there never a tricorder around when you need one?

[DonRocks]

I think the skill is more rare than phytolith analysis.

Edit:  I assumed you were asking about skill sets relevant to the work, not things like teaching, mentoring, problem solving, etc.

Yes, and bulliform me for being rooted enough to ask such a silic question.

[DonRocks]

A typical day starts at home where I caffeinate myself, try to wake up, and answer emails until the traffic has cleared off my route.  Then I head in to the lab.  If I have samples to study, they are almost always residues that I extract from artifacts, groundstone and flaked tools or ceramic sherds, or sediment samples, bags of dirt collected from various contexts that may be related to plant use.  I try to make the most of lab time by scanning slides on the microscope while the next set of samples is processing on the bench top.  By its nature, microscope work is time-limited.  Eye fatigue can come on quickly while scanning in search of tiny objects, so I don't do more than six samples in any one sitting.  Missing something after spending all the time and effort to extract the data would be a terrible loss.  Right now I'm working on samples from an Archaic site in central Texas, and many of the artifacts are burned rocks from cooking hearths and discard features.

Tell me to stop whenever I go too deep, please.

These samples that you study ... do you collect them yourself? Or are they sent to you from field workers, much like an x-ray is sent to a radiologist for unbiased evaluation, "never having met the patient?"

Radiologists are well-paid, and also must carry boodles of malpractice insurance - are there any similarities, or do you ever get a chance to collect your own samples and do your own field work?

Assuming specimens are simply handed (or mailed) to you, what is the chance of them being tainted by the time you receive them? Do you often miss obvious things? Are your readings peer-evaluated by others in your field? There's so much that could go wrong, from simple human error, to malevolent manipulation of slides for grant-grabbing. This is all theoretical, of course, but it seems very much like a real possibility to me.

[lperry]

Similarly, besides assumptions about available Calories from changes like the lactose tolerance mutation, or the introduction of potatoes, what sorts of ancient dietary shifts (if any) should be of blockbuster interest, beyond the customary grade school handwaving of "hunter-gatherers settled down"?

With apologies to the raw food movement, one of the most important shifts in our food history was when hominids began cooking their foods.  Richard Wrangham and others out of Harvard University have suggested that cooking roots and tubers was key in the development of both modern human social structure and important physiological adaptations "“ you can read the article in Current Anthropology here.  The authors place cooking at about 1.8 million years ago, and it should be noted that this model is controversial.  It is widely agreed upon, however, that there was great significance in the increased availability of nutrients in cooked foods over raw.  Much less time and effort is spent for a higher gain.

[lperry]

Also, other than Otzi the Iceman and I imagine some Siberian mammoths, are there any other stomach contents of interest from *really* ancient remains?

Not to my knowledge, but I guess it also depends on what *really* ancient means to you.  I have a book on my shelf called "The Bog People" that documents the recovery of the bodies of executed people who were placed into the bogs of Denmark where they lay, perfectly preserved for more than 2000 years.  The pictures are kind of creepy, and the peat harvesters who discovered the first ones thought they were modern murder victims.  The Denmark stomach contents are full of seed and grain-based gruel, and the oldest bog remains yet found in Europe are 8000 years old.  Not terribly ancient, but some of the best preserved stomach contents out there.

And finally, tossing in a Weekly World News question: what do you make of the recent attempt to identify the flora depicted in the controversial Voynich manuscript?

I find it interesting that modern researchers rarely if ever consider the possibility that people in the past may have had a sense of humor.  Or were a little nutty, for that matter. 

[ol_ironstomach]

Thanks for the memory jog.  Back around high school, I had read a few articles about the mystery and eventual identification of the origins of the bog people, but nothing about their stomach contents.

With apologies to the raw food movement, one of the most important shifts in our food history was when hominids began cooking their foods.  Richard Wrangham and others out of Harvard University have suggested that cooking roots and tubers was key in the development of both modern human social structure and important physiological adaptations

As someone who has hosted a gently humorous tuber-themed dinner party for most of the past 17 years, I can't tell you how pleased I am to learn this!  Nor do I recall ever being so intrigued by starch grains in a non-photographic context...the sleuthing that you do is really, really cool.

[ATF]

Not sure if it is too late to post a question, and an answer might be readily available elsewhere. But just in case you are still responding:

Is there a consensus as to whether beer led to bread, or bread led to beer?

[lperry]

Linda -  fascinating discussion.  Here's something I've always wondered about, which may be a bit tangental to the discussion so far, but I'll ask anyway.  I've always wondered how early humans found and got focused on the things that turned out to be useful or desirable for food, drugs, whatever.  Somewhere above I think you mentioned there have been perhaps 30,000 plants used as foods; yet there must be many times that which aren't useful to humans for food.  So the good ones had to be sorted out from a lot of contenders.  Obviously there must have been lots of trial and error, but how did they go about this trial and error process?  How did the process unfold?  How many things had to be tried to find the few that turned out to be useful, and how did ancient peoples measure which ones those were?  Surely there was more to it than just random natural selection!  In particular, how were things discovered where non-obvious processing is needed, like adding lime to corn, or fermentation of soybeans to make sauce (I know it happens naturally, but still....).

I'm reminded of that old phrase about he being brave the first man to try an oyster.

Hi johnb, and thanks for taking part in the discussion.  The short answer to your question is, we can't really know unless there is a written history.  The long answer is, there are some logical possibilities as well as some mythologies to study, and it can be fun to think about how things may have happened.

My favorite story about people figuring out an interesting food is the one about the Ethiopian goats and coffee.  Who doesn't love dancing goats?  Even though it may not be true, it does represent a highly probable method for ancient humans seeking foods, and that is to watch what the animals are eating and follow their lead.  The first person to eat an oyster may have seen an oystercatcher bird eating them.

For the more esoteric processing, it's more difficult to know.  I was asked about the nixtamalization processing in my prelims (scary flashback) and have thought about it and other complex processes since.  Here's my hypothesis for that particular process: Modern people use cal to process maize, but anything really alkaline works, so wood ash was probably the original chemical.  Someone boiled maize in a vessel that happened to contain ash from a fire, and found that the hulls came off the corn kernels.  As someone who has spent time grinding seeds with stone tools, I know that making the process easier would be an excellent motivator for invention, and this maize was certainly easier to grind than maize with hulls.  So the accident turns into an invention, and the person tries drying and grinding the hulled maize.  Time passes, and a few people are grinding maize that has been treated with ash, and, in addition to the relative ease of processing, they find the breads they make hold together better, and further experimentation leads to thin, very tasty breads that can be wrapped around foods.  Some neighbors don't want this new bread, others do, and the process moves out a bit from the center of invention.  After a few weeks or months, it is noticeable that the families using this new method also have kids who are healthier than everyone else because, just as a side effect of the process, more nutrients are released.  Everyone wants healthy kids, so people learn about this new method, and it spreads farther via word of mouth and intermarriage.  And so on, and so on.

That's my take on it.  People worked hard for their food, they were just as smart as we are, and, arguably, more in touch with their environments.  Observation, experimentation, step by step changes in the process to make it better, and adoption of what made life a little easier, better tasting, or healthier are the drivers that I think were important in developing some of these processes.  Someone else may give you a different answer.

[zoramargolis]

To piggyback on the fascinating information you have provided above: I have been amazed by the process of nixtamalization, mostly because I have loved the flavor of nixtamal/masa since I was a young child growing up eating Mexican food in Los Angeles. But turns out that the process liberates niacin and prevents pellagra, which the early corn cultivators figured out. When corn spread around the world, that piece of knowledge and tradition was missing, and pellagra became a common disease in poor populations which derived most of their calories from eating corn, in Europe and the American South.

Another bit of culinary wisdom of the same population, albeit without the public health benefits of nixtamalization is tequesquite, a mineral salt gathered from the edges of alkaline lakes in Central Mexico, used to cook beans to soften their hulls, and to leaven tamales. Baking soda, in its natural form.

As smart as we are? Maybe smarter.

[johnb]

,,,,,, it does represent a highly probable method for ancient humans seeking foods, and that is to watch what the animals are eating and follow their lead.  

This inspires me to wonder how the fellow who discovered kopi luwak went about making his discovery.  Brings new meaning to "following their lead."

[lperry]

And, the answer was  . . .?

The answer started with a really boring, adult, learning-moment response about gross things usually being made of organic matter, and all the microorganisms in the soil decomposing them long before archaeologists can excavate them.  Then I told him about the summer in Texas when the most promising site found in our field school survey was in a field that had been overrun by feral pigs, and how the first foot or so of digging involved working through some rather thick, fragrant, organic matter.  If I had ever worked on a medieval cess pool, I would have had a better story.  Maybe.

[Barbara]

The answer started with a really boring, adult, learning-moment response about gross things usually being made of organic matter, and all the microorganisms in the soil decomposing them long before archaeologists can excavate them.  Then I told him about the summer in Texas when the most promising site found in our field school survey was in a field that had been overrun by feral pigs, and how the first foot or so of digging involved working through some rather thick, fragrant, organic matter.  If I had ever worked on a medieval cess pool, I would have had a better story.  Maybe.  

I actually wasn't expecting an answer, but thank you. This entire discussion is really fascinating for so many reasons. That you are trying to parse the actuality--as opposed to modern assumptions and prejudices--is far more interesting to this crowd than you might have imagined.

To pick your brain some more, have your read Jared Diamond's Guns, Germs, and Steel?, and, if so, how can you expand on his theory that ancient people all across the globe figured out what was not only edible but cultivatible (not right word, but you get my drift) because of your research?

[lperry]

Do you have a more bounded specialty within your field, like expertise based on

- a certain geography

- a certain time period

- a certain group of associated researchers

- the whims of your funding source?

- or other, or not at all? (I suppose Archeobotany is fairly specialized to begin with)

Sliced another way, why would someone in need of Archeobotanist call you vs. another Archeobotanist?

You are correct in your assumption that archaeobotany is fairly specialized, and some researchers spend their careers in one area, or even on one, large site.  There is certainly enough work to occupy researchers for multiple lifetimes in any site.  For a variety of reasons, my career has run in many different directions, and, at this point, I have worked on six continents at sites that date from more than 11,000 years ago to about 100 years ago.  I feel incredibly lucky to have been invited to work on so many interesting projects.

People call me because they are interested in the methods I use, particularly the starch grain analysis which is very useful in recovering plant remains in contexts where other categories of plant remains either may not survive, or may be unusual.  The basic methods are pretty much the same in any site.  The differences lie in learning a new set of comparative materials - a new flora, if you will - for the purposes of making identifications and interpretations for the site.  That's one of the wonderful things about this work.  I spend all my time learning.

[lperry]

These samples that you study ... do you collect them yourself? Or are they sent to you from field workers, much like an x-ray is sent to a radiologist for unbiased evaluation, "never having met the patient?"

I have collected my own, but these days, they are sent to me.  I specifically ask that the excavator keep information from me until I have my results and have made my identifications.  There's a really bad joke: like all microscopists, I prefer to work blind.

Radiologists are well-paid, and also must carry boodles of malpractice insurance - are there any similarities, or do you ever get a chance to collect your own samples and do your own field work?

I don't understand the connection between the first part of the question and the second, so I'll say that I don't think I'm particularly like a radiologist, although I do find x-rays interesting.  I'm pretty sure most people think of me as "the lab specialist" and don't even consider the possibility that I might be interested in excavation anymore.  I enjoy fieldwork, and I should probably be more proactive about getting myself written into that part of the grant proposals that come my way.  Part of the issue over the past few years has been having elderly pets, and not being willing to leave them for long periods of time.  I lost my little orange cat at 17 last Thanksgiving, and his sister, my tortie, who is snoring softly here next to me, will be 18 in April.  It's not fair to caretakers or to the animals to leave them for so long, so I stay here and do labwork.  That may be changing soon, I fear.

Assuming specimens are simply handed (or mailed) to you, what is the chance of them being tainted by the time you receive them? Do you often miss obvious things? Are your readings peer-evaluated by others in your field? There's so much that could go wrong, from simple human error, to malevolent manipulation of slides for grant-grabbing. This is all theoretical, of course, but it seems very much like a real possibility to me.

I'm not sure what you mean by tainted.  Contaminated, maybe?  There are protocols in place to prevent contamination from occurring from the moment something is collected in the field until it gets to me or any other analyst.  Those following modern methodologies in the field are very careful because they want the information collected properly so they can have the best understanding of the context.  I am frequently asked about field methods for "clean" collection of samples, so I believe that most researchers are doing their best to keep the data intact.

I hope I don't miss obvious things, but if I did, I would be unaware of it, because I missed it, so I can't really know the answer to that question.  Everything I publish is peer-reviewed, usually by three reviewers, as is anything published in an academic journal, so there are people double checking my and everyone else's work, if that's what you mean (?)

I think that the malevolence of people, assuming there is any, comes out in the review process rather than in any manipulation of data.  Someone who doesn't care for you or your work may, for example, tell an editor to reject a paper, or a granting source that your proposal should not be funded.  A very wise advisor once told me that there are jerks in every profession, so you may as well do what you love to do.  It has been my experience that people who go looking for a fight are really good at finding one.  I go looking for peace, love, and excellent data.  What else can you really do?  

[lperry]

Not sure if it is too late to post a question, and an answer might be readily available elsewhere. But just in case you are still responding:

Is there a consensus as to whether beer led to bread, or bread led to beer?

Hi ATF.  It's not too late, and the answer is, no, there is no consensus.  There are people who believe the first beers were made using fragments of bread, and others argue that beer was first, and was not really what we think of as "beer" today.  It was, rather, a slightly fermented gruel that was more nutritious than the unfermented variety.  I'm not going to jump into the fray until we have more hard evidence.