Fire Up Your Hearth: Relax & Stay Warm (While Being Energetically Inefficient)

My lab & I have presented on & written about fireside relaxation so many times by this point that I’m running out of clever titles. However, now that our first paper has finally been published &, as it happens, at the perfect time of year, I want to share an annotated press release.


Press Release

“Hearth and Campfire Influences on Arterial Blood Pressure: Defraying the Costs of the Social Brain through Fireside Relaxation”

A University of Alabama anthropologist has found that, consistent with anecdotal reports, hearth and campfires can be relaxing and suggests this influence on the stress response system may have been important in the evolution of the human social brain.

In a recent article in Evolutionary Psychology (, Christopher Lynn, a medical and psychological anthropologist, reports preliminary results from a three-year lab-based study.

Lynn isolated the sensory aspects of fire to study its influence on blood pressure before and after subjects watched a variety of simulated conditions, including a Yule fire DVD with no sound, or a Yule fire DVD with sound, a blank computer screen, and a static upside down picture of a fire. They found significant decreases in blood pressure associated with the more naturalistic conditions and longer exposure duration. On the other hand, fire with no sound and the upside down picture of a fire seemed to agitate subjects and increase stress.

Lynn and other researchers believe the relaxing influence of fire may have been important in human evolution. As claimed in the 2013 Coke Zero ad “Civilization,” featuring fur-clothed males in front of a fire, “man has always been captivated by watching stuff. And as civilization progressed, man was able to watch even more riveting stuff. And now scientists have developed HD to romance your eyeballs. How can you look away? So relax and do what your brain was meant to do, watch stuff.”

Tongue in cheek as this commercial may have been, recent findings suggest the human relationships with watching fire may have begun as early as 1.7 million years ago. Surprisingly though, no studies have examined the influence of fire on human cognition until now, confirmed that fire is a source of relaxation as commonly ascribed, or investigated the elements that produce its relaxing effects.

Lynn also found that greater relaxation effects were experienced by those who scored higher in prosociality. This finding supports speculation that manning perpetual fires before humans developed the ability to kindle them may have led to enhanced cooperation.

Stress-related disorders are among the leading causes of disability in the modern era and pose significant economic impacts worldwide, so it is important to better understand evolved mechanisms and environmental triggers of stress reduction like that of fireside relaxation. Firelight may enhance capacities to become absorbed in an object of attention and influence relaxation via autonomic nervous system effects, especially at night.

In addition to this fine press release that I wrote about myself in 3rd person, some astute journalists & bloggers have found their way to the article in advance of my shameless self-promotion.

The blog “Seriously, Science?” posted a somewhat snarky piece (I think?) pointing out what an obvious finding it is that fire is relaxing (I think—& which I agree with, btw). S/he also is savvy enough to point out that an alternative conclusion might be that all participants were culturally conditioned to find fire relaxing. We did control for that, though in a way that might not be obvious & is not stated specifically as such. We controlled for growing up with a fireplace, going camping, & hours spent staring at computer screens & other—ahem—flickering light & sudden sound phenomena (smartphones).

I like the piece by Mail Online even more because it overinterprets the findings in a way that I wasn’t quite willing but which I think most of us evolutionists feel is not quite true. However, I do need to point out that I’m suspicious there is a quiet minority whose interest is fire is ‘meh.’ Hopefully, we’ll address this variation better in our next paper.

I’ve also had a few cool papers sent to me in just the few days since the article came out by others researching fire or fire-related aspects. One I like that peripherally relates but is something I’ve never ever thought about is by Keith Stephens-Borg, who, I believe, is a practicing anesthesiologist in North Devon, UK. His essay, “The Crystal Chalice: Investigating the Source of Fiberoptic Science,” traces the medically transformative science of fiberoptics (thank you, endoscopy Gods, for aiding in the diagnosis of my Barrett’s esophagus, which used to bring me debilitating pain & now is largely check with Prilosec)  to the changes in human perception & consciousness that came with the manipulation of fire.



Posted in Anthropology | Tagged , , , , | 1 Comment

Is Cunnilingus an Adaptation to Increase Intercourse Length & Increase the Probability of Fertilization?

Several years ago a student of mine (Christy McGee) in my “Anthropology of Sex” class was studying highly promiscuous women with the hypothesis that they would be averse to cunnilingus. She suggested that cunnilingus was a male means of detecting infidelity. I will admit my skepticism at the time, not because it seemed far-fetched but because it seemed so difficult to test. Instead, I pushed her toward considering a bonobo model to test whether there was any adaptive basis (read “phylogenetic” basis) for cunnilingus to begin with.

In querying the only person I knew who might have thought about this, Gordon Gallup, who was one of my grad advisers, had actually blogged on this very topic & posited that cunnilingus was a human cultural practice. He posited that bonobo (& chimp) vaginas would collect sweat & be the site of chemical warfare (between pathogens trying to get in & vaginal acids staving them off) that produced unsavory byproducts, such that, even if cunnilingus was experimented with by young apes, they would develop a learned taste aversion.

After visiting the Memphis Zoo & observing their bonobos, I concluded from the shape & position of bonobos labia that this scenario is highly unlikely. The orientation makes it physically implausible. I seem to recall discussing this in an early blog with photos, so I direct you there.

The only other experts I’ve ever mentioned this to looked at me like I was nuts (Frans de Waal—yeah, right? Frans de Waal of all people—even though he has the only data I could find on the topic, which he didn’t seem to recall publishing) & ignored me (someone at AAPA whose name escapes me). Nonetheless, after years of speculating about this in class & lab, one of my excellent & ambitious HBERG students, Erica Schumann, took on the project I’ve been proposing for years. She took videocameras to the Fort Worth & Memphis Zoos to record bonobo behavior & code specifically for cunnilingus!

On a sad side note: The lone male at the Memphis Zoo was unexpectedly separated from the several females when Erica went to collect data & subsequently died before she could return.

Okay, how do I follow that with what I’m excited about today? Well, more on her exciting (& arousing!) research later. But relevant to it, I saw this tweet earlier tonight:

And replied with a comment only a primatologist interested in sexual behavior could appreciate:

Male bats are using cunnilingus to render females receptive to copulation, either stimulating vaginal secretions or, you know, other stuff (what other stuff?).

Figure 1. Relationship between duration of pre-copulatory cunnilingus and copulation. Circles and numbers indicate average duration of copulation and n value, respectively. doi:10.1371/journal.pone.0059743.g001

Figure 1. Relationship between duration of pre-copulatory cunnilingus and copulation.
Circles and numbers indicate average duration of copulation and n value, respectively.

Watch them go! This is fascinating. And, honestly, is it possible that we’re unaware of the breadth of mammalian fellatio & cunnilingus because it’s practically impossible to see what’s going on when small furry animals in trees are doing the nasty? I mean, most don’t hang upside down like two shirts (with penises & vaginas) tangling up on a clothesline for us to watch.

(I can’t get the damn video to embed, so here is the link to it)

And this has me thinking, is human cunnilingus an adaptation to make females more sexually receptive? This seems like a stupid question, but, I guess what I’m asking, is it more than a cultural adaptation? Is it a case of convergent evolution, wherein two species have converged on the same adaptation to increase female receptivity where sperm competition is relatively high? And how can we test this?

Posted in Adaptation, Anthropology, Biological Anthropology, Hypotheses, Mating and Sexuality | Tagged , , , , | 2 Comments

Tuscaloosa is BEST: Prosociality in Tuscaloosa

This past spring I started a study called the Belongingness Ecology Study Tuscaloosa (BEST). Like the Religious Ecology Study Tuscaloosa (REST) before it & over which I consider it an umbrella project, it grew out of the readings & activities in an Honors seminar I teach called “Primate Religion & Human Consciousness” (PRHC; see the blog for that course here). More specifically, it grew out of reading the work of David Sloan Wilson & his students & collaborators. In the mid-2000s, David began the Binghamton Neighborhood Project (BNP) to apply evolutionary principles to improve communities in the city of Binghamton, NY. In the wake of this project, which has resulted in several papers & book on the work they’ve done, similar projects have sprung up in Boston (Boston Area Research Initiative), Flint, MI (see Dan Kruger’s publications for info on this study), Newcastle-on-Tyne (Tyneside Neighbourhood Project), & Madagascar (Positive Education Action-Research).

Inspired initially by hearing David speak about BNP at the EvoS Summit a few years ago (here is a link to the actual talk), when he said (paraphrasing here) that the application of evolutionary principles to improving the quality of life for people in his community feels more real & thus more important than any of the other evolutionary research he has done (which is massive & expansive) & is now his primary interest (forgive me, David, if I don’t have that quite right, but readers should watch the presentation & let me know if I got it right!). Generally, I like to be helpful, but I especially like it if what I already like to do is something people find helpful. As I often tell students, I’m not out to save the world—I study what interests me, but I try to find ways those interests can be of interest to others because it’s how I get funding. If it also improves my community, that’s an added bonus & increases the probability of funding. It’s this type of attitude that leads David & his coauthors to prefer the use of the term “prosocial” in their Evolution and Human Behavior paper “Human prosociality from an evolutionary perspective: Variation and correlations at a city-wide scale” (2009), which has led me to write this post.

…the term altruism has a strong connotation of self-sacrifice in addition to helping others. While helping others sometimes requires extreme self-sacrifice, often it is possible to benefit others at a low cost to oneself or to benefit along with others in the provision of public goods (Sober & Wilson, 1998)…We prefer the term “prosocial” to “altruistic” because it focuses on other- and society-oriented behaviors while remaining agnostic about the degree of individual self-sacrifice that might be involved. Thus, an individual who routinely does favors for others or who agrees with the survey item “I am helping to make my community a better place” qualifies as prosocial, regardless of the degree of self-sacrifice involved.

Our initial BEST efforts (ha ha) have been exploratory. I stepped back from encouraging students in the PRHC course to use the church-by-church study model we developed based on David’s book Darwin’s Cathedral (2002) &, following Barbara King’s model for the evolution of religion outlined in Evolving God (2007), I assigned them simply to study any group that inculcates “belongingness” & to assess the degree to which it does that. (Ironically, while past classes have shied from choosing churches as the focus of their study, this past semester’s class all chose churches.) The methodology they used combines cultural consensus & religious-commitment signaling theory, which I outline in an article currently in review (so I can’t spill the beans yet, but email if you’re interested in reading the current draft).

The biggest problem with this approach is that it requires a lot more work than can be accomplished in a semester. So, while I believe it is great experience for the students, the data are scant & ultimately lack utility for the larger project I have in mind. So, over this past summer & after conversation with Dan O’Brien about the BARI project at NEEPS 2014, which featured a whole session on these evolution-community projects, I switched gears & decided to focus attention on specific groups, based on some hanky-panky that went down here a year ago (see my post “University Greek Systems are Natural Experiments for Multi-Level Selection Theory (Waiting to be Investigated)” for more info on that). This semester, I have a student in my research group & another student I am supervising as part of a local government internship doing social network analysis of the University of Alabama Student Government Association & the City of Tuscaloosa City Council. Our hypothesis is that, analogous to brains, more networked groups are “smarter”—e.g., more capable of flexibility & getting more done. However, this project requires more people-power, so, as with my last post, I’m in need of a grad student to help handle the day-to-day running of the project & expand it beyond those initial two groups (please contact me for more info or apply!).

But, as I say, it is reading David & Dan’s 2009 article on the BNP that inspired this post. I’m intrigued by this principle & how we can use it to study the efficacy of cooperative groups:

Game theorists refer to a “replicator dynamic” as any process whereby the most successful behavioral strategy increases in frequency through time, which can include such things as learning and imitation in addition to genetic evolution (Bowles 2003; Gintis, 2000). Any replicator dynamic counts as an evolutionary process, vastly expanding the relevance of evolutionary theory to contemporary human affairs.

In the 2009 article, David & Dan outline a study of prosociality in Binghamton that involved analysis of data collected using the Search Institute’s “Developmental Assets Profile (DAP)” survey among Binghamton school children & replication of the lost-letter study to objectively validate self-reports re neighborhood quality. In the spring 2015, I am implementing a “service-learning” component of the PRHC course, which I intend simply to be an expansion on & elaboration of the BEST endeavor, so that the students can collect information that will be of use to policy makers in our municipality (which is the overall purpose of BEST). I am thinking of replicating David & Dan’s study, which will require the students to contact the school superintendent & BOE to request permission or assistance in collecting DAP data, writing up an IRB proposal (that will be unlikely to be approved before the end of the semester but could set up conditions to continue the study during the following semester), & conducting the lost-letter study, which a service-learning fellowship I received can subsidize.

We can do this for Tuscaloosa. How cool would that be?

Mapping Binghamton's prosociality with two different methods. On the left is a continuous map using kriging; on the right the city is split into discrete census block groups with scores. Both use the responses from the DAP. (From Wilson et al. 2009, DOI: 10.1016/j.evolhumbehav.2008.12.002)

Fig. 2. Mapping Binghamton’s prosociality with two different methods. On the left is a continuous map using kriging; on the right the city is split into discrete census block groups with scores. Both use the responses from the DAP. (From Wilson et al. 2009, DOI: 10.1016/j.evolhumbehav.2008.12.002)

Posted in Anthropology, Cultural Evolution | Tagged , , , , , , , , , , , , , , , , | Comments Off on Tuscaloosa is BEST: Prosociality in Tuscaloosa

Cognitive Evolution via Campfire Stories

A fantastic analysis of fireside conversations among Ju/’hoansi Bushmen collected over the course of four decades (1970s-2000s) was recently published by Polly Wiessner in PNAS Early Edition (“Embers of society: Firelight talk among the Ju/’hoansi Bushmen“—thanks to Daniel Lende & Michaela Howells for alerting me to this piece).

Several highlights make me want to find a grad student who wants to do fire research so we can expand upon our current lab-based & local study (& right before I “went to press” with this, I was giving a rundown to my virtual writing group & got a great field site suggestion from Cara Ocobock–apply to Bama & I will tell you more!).

…little is known about what transpired when firelight extended the day, creating effective time for social activities that did not conflict with productive time for subsistence…Night talk plays an important role in evoking higher orders of theory of mind via the imagination, conveying attributes of people in broad networks (virtual communities), and transmitting the “big picture” of cultural institutions that generate regularity of behavior, cooperation, and trust at the regional level. [from abstract, pg. 1]

Day talk centered on practicalities and sanctioning gossip; firelit activities centered on conversations that evoked the imagination, helped people remember and understand others in their external networks, healed rifts of the day, and conveyed information about cultural institutions that generate regularity of behavior and corresponding trust. [from “Significance,” pg. 1]

Wiessner plotted the location of protagonists in stories told around the fireside (except for those involving anthropologists! LOL). I wonder about the practicality of doing something like this with contemporary campers. Ethnography of one of those campgrounds where people rent a site & live there for extended periods, coming back year after year. Does the evening campfire have the same effect, even when they can retreat to their RVs? What is the effect of sitting around a fire with your smartphone in your hand? And, yes, I’m guilty of this too, checking out in the midst of a social circle (I know, shame on me).

Fig. 2.

Location of people who are protagonists in stories told by people from four different bands based at /Kae/kae. (Two stories about anthropologists not included). Number of stories from villages shown on map: Qangwa (n = 2), Dobe (n = 2), G!ooce (n = 4), Bate (n = 2), !Ubi (n = 1), Mahopa (n = 1), Sehitwa (n = 6), Nokaneng (n = 2), Tsumkwe (n = 9), G!anisha (n = 1), /Du/da (n = 2), Nxau Nxau (n = 1), Kaudum (n = 2), N = ama (n = 3), Due (n = 1), Eiseb (n = 1), G/am (n = 4), /Aotsha (n = 3), Bense Kamp (1), Gura (n = 2), /Uihaba (n = 1), N!omdi (n = 2), N=amdjoha (n = 1). (From Wiessner 2014

In most hunter-gatherer societies, firelit hours drew aggregations of individuals who were out foraging by day and provided time for ventures into such virtual communities, whether human or supernatural, via stories and ritual. Stories conveyed unifying cosmologies and charters for rules and rites governing behavior. These stories also conveyed information about the nature of individuals in the present and recent past, their experiences and feelings, as well as factual knowledge about long-distance networks, kinship, and land tenure. Stories told by firelight put listeners on the same emotional wavelength, elicited understanding, trust, and sympathy, and built positive reputations for qualities like humor, congeniality, and innovation. [7]

Here, specifically, are some research suggestions my lab is equipped to take on now (seriously, grad applications are being accepted):

…further research needs to be done on the physiological effects of different levels of firelight, including hormonal states and moods. Experimental work on the impact of body language and facial expressions by day and by night also might further understanding of why firelight mellows, bonds, and releases inhibitions in such a way as to facilitate journeys into imagined communities…the topics of night conversations in dyads or smaller groups need investigation…night conversation merits study to see if basic tendencies hold…

Posted in Anthropology | Tagged , , , , , , | Comments Off on Cognitive Evolution via Campfire Stories

New Paltz – A Beacon of Intellectual Freedom and of Evolutionary Studies

(this article first appeared as a letter to the editor in the New Paltz Times on 5/9/2014)

Dear Editor,

I write to give a status report on the Evolutionary Studies (EvoS) program that we’ve got at SUNY New Paltz – and to give a message of thanks to our broader community for allowing our work in the field of Evolutionary Studies to find such a supportive home in this special place.

In 2007, SUNY New Paltz started the world’s second academic program in the field of evolutionary studies – this program began with a group of faculty from such diverse areas as anthropology, biology, geology, psychology, and theatre arts. Inspired by Darwin’s vision of seeing the entirety of life connected within a single powerful and humbling perspective, EvoS New Paltz embarked on a journey to bring the ideas of evolution to students across any and all academic disciplines.

As part of this intellectual journey, we started (in Spring of 2008) the annual EvoS Seminar series (supported largely by CAS – Campus Auxiliary Services) – a speaker series featuring intellectuals who address various areas of inquiry in a way that relates to Darwin’s big idea. Since its inception, this series has included more than 50 major-league intellectuals – from various academic disciplines. These speakers have included Natalie Jermijenko (notable artist and environmentalist at NYU), David Sloan Wilson (biologist from Binghamton and originator of the EvoS idea), Robb Wolf (author of The Paleo Solution and a world-renowned voice on the topic of nutrition and exercise), Richard Wrangham (anthropologist at Harvard – and one of the most famous living primatologists), and Marlene Zuk (biologist at the University of Minnesota and one of the world’s most significant living biologists) – and many more.

I want you to know that nearly all of these talks have been videotaped and are now live-streaming (for free) thanks to the outstanding work of New Paltz’s office of Instructional Media Services (with special thanks to Keron Lewis). These talks are regularly taped via Mediasite software – and in 2011, we won an award for our Global Outreach from their parent company, Sonic Foundry.

The award we won from Sonic Foundry is significant in many ways – and it owes largely to the work of a major National Science Foundation grant that we were awarded (along with Binghamton – with essential roles played by New Paltz biology professor Jennifer Waldo and New Paltz psychology professor Rosemarie Sokol-Chang – and David Sloan Wilson, Director of EvoS at Binghamton). Working together, we worked to cultivate our speaker series – and to create a website for the EvoS Consortium – (currently managed by New Paltz psychology graduate student, Briana Tauber), has received well over 100,000 page views since its inception – and it includes the world’s largest database of free-and-streaming videos related to the topic of evolution. Yes, the world’s largest.

Given how intellectually rich our community is, New Paltz is, not surprisingly, at the forefront of evolution education – and, importantly, is at the VERY forefront when it comes to evolution education outreach. The support of the university – and of the broader community that we call home – has been absolutely foundational in allowing this to be the case. And in case you didn’t realize how central our little town is in shaping the nature of evolutionary studies in the field of education on a global scale, I just wanted you to know.

Thanks a ton to the broader community for your support and for allowing EvoS New Paltz to grow as it has.


Glenn Geher, Director of EvoS – State University of New York at New Paltz

Posted in Evolution in Higher Education, Glenn Geher, Uncategorized | Comments Off on New Paltz – A Beacon of Intellectual Freedom and of Evolutionary Studies

Gettin’ Down & Dirty with Dr. Dana: Xiphactinus, Enchodus, & Other Cretaceous Chalk Critters

Harrell Station Paleontology Field Site

Harrell Station Paleontology Field Site

I’ve been wanting to go fossil-hunting since arriving in Alabama, as I keep hearing about the wonderful locations down here, & finally got to experience this particular cheap thrill thru evolution. Our friend & Alabama Museum of Natural History Paleontology Curator Dana Ehret was kind enough to take me & my family down to Harrell Station to sift thru the chalk during our spring break.

Hunting fossils with (clockwise from left) Dana Ehret, my son Jagger, me, & my son Lux. My son Bailey & wife Loretta are not pictured. (Photo by Loretta Lynn)

Hunting fossils with (clockwise from left) Dana Ehret, my son Jagger, me, & my son Lux. My son Bailey & wife Loretta are not pictured.

Various parts of Alabama have been oceanfront property at various points in prehistory. Tuscaloosa, in west central Alabama, where we live, was oceanfront during the Cretaceous, so much of the area south of us is rife with deposition fossils. Harrell Station is an old railway station with 166 acres nearby owned by the ALMNH as a Paleontology Site. It is old eroded farmland where the topsoil has washed away & exposed the underlying geological formation called the Selma Chalk. This deposition was formed when the area was a relatively shallow & calm sea. According to an article about the site published just after it was purchased by the Board of Regents thru a fundraising effort, a series of papers published from 1948 thru the 1970s were based on fossils collected in just one month. Major dinosaur, mosasaur, & other fossils have come out of the site over the years. Though much of the bigger finds on the surface are likely gone, there are thousands & thousands of other small fossils surfacing regularly.

Bailey digging.

Bailey digging.

Dana has only been on staff a few years &, as one of the few with access to the site, has the luxury of this site as his playground practically any time he wants. In fact, the EvoS Club may be organizing a fossil-hunting camping trip there right now. But let’s do it before it heats up around here.

We managed to get out of the house around 10:30 (we’re not early risers, especially on spring break) & got to the site around 11:30. We parked the van in an adjacent cow pasture & went ahead & ate lunch. There is a gully exposure just a few feet from where we parked, but Dana wanted to take us to a site in the back because he takes most kid groups to the closer exposure so they won’t have to walk far. That means the back site is less picked over. Still, it was probably less than a half mile walk to the back exposure.

Selfie of me & Luxie showing off our tools & treasures.

Me & Luxie showing off our tools & treasures.

As Dana explained, the tendency is for people to run to the furthest areas, expecting them to have been less picked over, to make the more glorious finds. In doing so, everyone tends to run past the fossils in the front. People also tend to enjoy the mounds sticking up, but it is the lower flats where everything has washed down that most things settle.

So, I went straight to the back to seek my glory, missing thousands of fossils underfoot no doubt as I went. My kids jumped from mound to mound pretending they were on the moon & digging with trowels & a pick-hammer along the way. For my trouble, I found two decent shark teeth.

Jagger was smart enough to follow around the expert & learn how to do it right.

Jagger was smart enough to follow around the expert & learn how to do it right.

Actually, my son Jagger was smart enough to tag along behind Dana. As a result, he made the find of the day, a full vertebrae from a Xiphactinus audax, a species of 15-20 feet long predatory fish of the late Cretaceous. Either because he was just totally into the whole adventure or because he made the coolest find, Jagger loved fossil hunting, which is awesome, as I hope to have at least one little buddy to drag back out with me next time we get a chance. I was a proud dad the next day too to see that he’d made the Fossil Friday find:

Jagger found this vertebrae from a Xiphactinus audax, a 15-20 feet long predatory fish from the lower Cretaceous just sitting on top of the chalk in a gully.

Jagger found this vertebrae from a Xiphactinus audax, a 15-20 feet long predatory fish from the lower Cretaceous just sitting on top of the chalk in a gully.

When the Lynns pooped out from sun exposure (the sun reflecting back up off the chalk can be killer) & were reclining in the shade admiring my two teeth, Dana kneeled down in the nearby flat he’d indicated originally & found half a dozen shark teeth, Enchodus teeth, & fish vertebrae in 5 minutes. Now that we were all tired from running all over the moon, we had the patience to follow his advice, hunker down in one place, & started to find several more small pieces. I found a number of Enchodus teeth as well, & Dana found a piece of Mosasaur he gave me for my collection to show students.

Like any hands-on activity, what had formerly been rather difficult to remember & keep in context is now very clear to me because I can see it around us. On the way back, Dana pointed out the pines that love the chalky soil & indicate where Cretaceous depositions lie. Given that the beachfront gradually moved south over the eons, I wondered aloud if there are any Eocene, Miocene, or Oligocene depositions exposed where we might find primates.

Loretta with the 60-75 million year old Goblin shark teeth I found in her mouth.

Loretta with the 60-75 million year old Goblin shark teeth I found in her mouth.

Down near the first Alabama state capitol, St. Stephens, there are Eocene & Miocene depositions, he says, though he doesn’t know of any primates or protoprimates findings there. However, there is a site near Meridian, Mississippi, which is just about an hour southeast of Tuscaloosa, called the Red Hot Truck Stop Locality that has elicited omomyid teeth. Omomyids are crown primates, meaning they are among the very first families of animals in the fossil record that can be identified as primate ancestors. Dana has not been to the Red Hot Truck Stop (which seems weird, as Dana, like us, is definitely a lowbrow haute couture kind of person), but Chris Beard (he of Eosimias fame–OK, famous in fossil primate circles, but I’ve taught his book & discuss Eosimias every year as a possible base ancestor) has published on the findings.

My booty for the day. Damn, no primates during the Cretaceous? And what did I collect more of than anything else? Fossilized worm burrows that looked like turds turned to pyrite. And I picked up a real turd too. It was desiccated but still...definitely.not.a.fossil.

My booty for the day. More of than anything else, I collected fossilized worm burrows that looked like turds turned to pyrite. And I picked up a real turd too. It was desiccated but still…definitely.not.a.fossil. (Photo by Chris Lynn)

When I got home, I pulled up a recent article in which Beard describes the numerous species found at the site. First, the Red Hot Truck Stop Locality was literally a well-known truck stop, & there is at least one website lamenting its passing. Behind the building that, I believe, still stands & now houses another business, is the exposure to which some have access.

A whole host of fossils have been described from the Red Hot site (just Google Red Hot Truck Stop & look at it all!), but I had no idea that, according to Beard (2008) the most basal species of omomyids (Teilhardina magnoliana), who flourished after the Paleocene-Eocene boundary, had been found near here. Omomyids & the other Paleocene-Eocene crown primates the adapids are always a bit difficult to teach, as they don’t grab most students the way the fossil hominids do (well, some of the students), but I am excited to be able to now connect one of them to the local landscape & a site (the truck stop restaurant, that is) that the local kids may actually know firsthand!

Driving thru cotton fields on our way home, we stopped to take a picture in front of what looks to be a share cropper's cabin. (Photo by Chris Lynn)

Finally, driving thru cotton fields on our way home, we stopped to take a picture in front of what looks to be a share cropper’s cabin. A reminder of where we are. (Photo by Chris Lynn)

Posted in Paleontology | Tagged , , , , , , , , , , , , | Comments Off on Gettin’ Down & Dirty with Dr. Dana: Xiphactinus, Enchodus, & Other Cretaceous Chalk Critters

EvoS Will Lead to (Good) Transformative, Lifelong Experiences

Maybe that’s a stretch, but I don’t think so. I just had to share this tweet the president of the UA EvoS Club sent out last week during the Sarah Tishkoff lecture. She just turned 21 last week, so maybe she was a  bit tipsy, or maybe my promises of synergy & glory are coming to fruition.

Posted in Evolution in Higher Education, Evolution in the Classroom | Tagged , , , | Comments Off on EvoS Will Lead to (Good) Transformative, Lifelong Experiences

We Need Neandertals or Some as Yet Unknown But Genetically Similar Population Within the Last 100 ky in Our Story

A couple years ago when I first started blogging here, my friend John Edvalson asked me right out of the gate my opinion on the Neandertal-sapiens interbreeding controversy. I think I skirted an answer because, though as a biological anthropologists I thought I should probably have one, I was behind the curve & didn’t feel informed enough to say anything.

Things haven’t really changed, but I’ve always been uncomfortable with this whole interbreeding-with-Neandertals scenario. It makes for good play in the media, but it feels too tidy for me. Real human stories are just never that tidy. Take for instance, as geneticist Sarah Tishkoff just pointed out in her talk with my class & her ALLELE lecture yesterday, the plethora of new Homo species we keep finding–Denisovans, floresiensis, erectus gets demoted as regional variation of ergaster. A messy playing field. Given the ring speciation we see among other genuses in relatively small areas, that just makes more sense to me & that even most people with access to planes, trains, & automobiles still don’t really travel that far from home when they grow up & marry, it seems odd that Homo sapiens got their hands on the ring of power 200 kya & just came out of Africa kicking ass & taking names away.

But I don’t see many people posing the counter-argument lately, since the Neandertal & human genomes have been published. I keep wondering, why is 2% of Neandertal DNA evidence of interbreeding? Why isn’t it just evidence of shared ancestry? In fact, I’m pretty sure I pressed John Hawks on this when he was here a few years ago, but I forgot his answer. The continued barrage of news media & even scientific party-line towing about interbreeding had pushed it from my mind. So when Jim Bindon sent this blog post around, I thought–aha! here’s someone bold enough to articulate my confusion. So I dutifully posted it on my Facebook wall, got a bevy of my biologist friends scoffing at our ignorance (but still not explaining this to me in terms I could understand), & got John to rearticulate his position, but in writing this time!

All of us have shared ancestry with Neandertals. Some have more than others. Indicates ancestry from a population more like Neandertals than any living people are. Who was that population? One possibility is Neandertals. Another is one or more ancient non-Neandertal populations that were genetically more like Neandertals than anyone living now. Length of chromosome blocks that are similar to Neandertals suggest that this similarity comes from a population that existed within last 100,000 years. So we need Neandertals, or an as-yet-unknown population that was genetically similar to them within the timeframe that Neandertals existed, and lived somewhere that sub-Saharan Africans could have mostly avoided them.

THIS makes sense to me, given the evidence. Maybe it’s just because he’s an anthropologist & knows how to speak my language. I know John is a big Neandertal supporter, & I get why (besides the fact that he’s a paleoanthropologist & geneticist who actually knows the data from the inside to a degree most of us will never have access to). H. neandertalensis has been knocked around for too long–why COULDN’T they have interbred w/ other Homo? Clearly, they were not dumb, as pop culture tended to depict them. I’m with him on that.

John impressed me during his talk at Bama with many things I hadn’t known about them, such as that our knowledge of them from European samples is probably from a later backwater of their own population, which may have been centered more in Asia, where they were probably also much more genetically diverse. But bonobos & chimps are genetically MORE similar & haven’t interbred for, what, 3 million years?

Shedding more light on this, as many of you know, are two new papers out last month in Science & Nature. One of the key points is that this 2% of shared DNA is in non-African populations.  The sticking point is that, while this is compelling, we have only sampled a small proportion of the African genetic diversity yet, which constitutes 2/3 of the genetic diversity worldwide, & most of those samples come from Yoruban populations, who are connected to the Bantu expansion. This point was made clear in a great talk this past Thursday at Bama by geneticist Sarah Tishkoff.

Tishkoff’s story is great. I was going to write up a separate blog post about it, but I’ll detail a bit here. Why don’t we know more about African genetic diversity, many people ask her? She explains this by showing slides of her fieldwork. First, let me say that she has truly impressive credentials. She was trained as an undergraduate in Allan Wilson’s lab at UC Berkeley & worked with the very first PCR machine. She did her graduate work with Kenneth Kidd at Yale & did a postdoc at Penn State. Despite starting in Anthropology, it wasn’t until her postdoc that she got to experience her dream of doing fieldwork. She was lured to study the genetic diversity of African hunter-gatherers because it’s so understudied. Even at that point, because of political issues, it took her 6 years to get the permits & funding to begin the data collection. Then she had to set up a lab in the bushes, literally. Working in field settings with no electricity, they use truck batteries to power centrifuges.

Anyway, Tishkoff’s work indicates that we can see selection in the genome, & we can see admixture in the genome as a result of migration (together with linguistic, phenotypic, & archaeological data). For instance, she has found evidence of lactase persistence genes that mutated in E. Africa & are distinct for mutations associated with lactase persistence among Europeans. Those mutations show up in S. Africa but at a much lower rate, indicating migration by some E. Africans to S. Africa & some admixture (in press, J Hum Gen).

So, IMO, the jury is still out on who bred with who, but the genetics, like the fossil record can get us there. Until we collect more data, however, all the current theorizing is essentially speculation, &, I fear, the sexiest interpretation will continue to hold the spotlight until the evidence catches up. And what is sexier than actual sex?

Posted in Biological Anthropology, Genetics | Tagged , , , , | Comments Off on We Need Neandertals or Some as Yet Unknown But Genetically Similar Population Within the Last 100 ky in Our Story

Modeling Recent Human Genetic Adaptation

Geneticist Dr. Sarah Tishkoff from the University of Pennsylvania is speaking as part of UA’s ALLELE series today, & EvoS students are reading a recently review she co-authored for Nature with Laura Scheinfeldt for the occasion. The piece, “Recent human adaptation: Genomic approaches, interpretation and insights,” is excellent in general in conveying the complexity of study recent human evolution. In particular, I like the figure they include to depict ways recent genetic change can be modeled.

Posted in Genetics | Tagged , , , | Comments Off on Modeling Recent Human Genetic Adaptation

Let the dead bury the dead?

Many years ago, I was watching one treacly movie or another about a grieving widow. It wasn’t good, but it was embarrassingly effective. I was moved. As I am wont to do, I quickly dissipated my sadness by contemplating a (superficially simple) question: Why do we, as humans, grieve at all. I had, at this point, thoroughly imbibed the evolutionary psychology literature and I approached human behavior from a relentlessly Darwinian perspective. Grieving, I thought, is costly and it is not so obvious what return a griever could expect from his or her anguish. Putting the question this way may seem unduly callous and excessively analytical. Grief is a powerful human experience. Why kill it so we can perform an autopsy on the lifeless cadaver? Putting aside a suite of powerful rationalizations, I will simply confess that the subject piqued my curiosity. I wanted to understand why we might possess a capacity to grieve.

Many years later, my colleagues (Tania Reynolds, Roy Baumeister, Ben Winegard, and Jon Maner) and I believe we may have discovered one possible solution to the puzzle of grief.

We begin by noting that grief is indeed puzzling:

 “A bereaved wife every weekend walks one mile to place flowers on her deceased husband’s cemetery stone. Neither rain nor snow prevents her from making this trip, one she has been making for 2 years. However poignant the scene, and however high our temptation to exclude it from the cold logic of scientific scrutiny, it presents researchers with a perplexing puzzle that demands reflection. The deceased husband, despite all of his widow’s solicitude, cannot return to repay his wife’s devotion. Why waste time, energy, effort, resources—why, in other words, grieve for a social bond that can no longer compensate such dedication?”

 Although this is a poignant tableau, the real costs of grief might be much more severe:

“It may require significant interruption of a person’s ability to perform daily tasks, to participate in social activities, and to seek out romantic partners (Archer, 1999; Averill, 1968; Schwab, 1992). Grief also increases mortality rate, susceptibility to illness, visits to physicians or other health professionals, suicidal ideation, and possibly even suicide (Fredrick, 1971; Hart, Hole, Lawlor, Smith, & Lever, 2007; Maddison & Viola, 1968; Parkes, 1964; Parkes & Brown, 1972; Phillips et al., 2006; see also Hendrickson, 2009 for a cautious review of the literature on parental grief and health).”

From an evolutionary perspective, these costs are puzzling because they would appear to reduce one’s inclusive fitness–especially because the ostensible target of the displays, namely the deceased, cannot possible recompense the mourner’s dedication (the sadness, longing, et cetera).

But what if the real target of the displays is someone else? Perhaps, that is, grief is a signal that is directed not at the dead, but at the living. Grief, then, might be a signal of (1) one’s underlying propensity to form strong, stable social bonds and/or (2) one’s current level of commitment to a group/tribe. We believe this is one possible reason for the existence of humans’ prolonged grief response. Our scenario for the evolution of grief is as follows:

  1. The original grief response was a byproduct of the attachment system. At first, the grief response was probably relatively muted compared to today’s average grief response.
  2. Observers began to note (not consciously) a correlation between a person’s grief response and his or her general propensity to form strong social bonds (or between the grief response and the person’s commitment to a group.)
  3. Observers began to make social decisions based on the grief response
  4. The grief response was shaped and elaborated by those decisions just as trees and flowers were shaped and elaborated by the preferences of pollinators.


Grief, then, separates/d the social wheat from the social chaff. Of course, this is a speculative reconstruction of grief, and it is not without problems. Robert Kurzban wrote an excellent blog (see bottom for link) in which he forwarded two basic objections to this proposition. The first objection was that there doesn’t seem to be an asymmetry in costs between a prosocial griever and a more exploitative non-griever. The second was that our proposal relies upon signaling “types,” or relatively stable personality characteristics that persist across domains (e.g. a general “prosocial” personality). These criticisms are insightful and important, and I am thankful that he raised them. Although I concede that they might be entirely correct, I would like to forward a few possible answers. Let me tackle them in order.

We argued that grief is a costly signal that has different costs for a loyal person who has a propensity for forming strong social bonds than for a relatively disloyal person who does not. That is, we argued that a person who forms strong commitments faces relatively fewer costs for grieving than does a person who is unlikely to form strong commitments. Kurzban argues that this is implausible:

“It seems clear that the woman in question has more than just the two options of either grieving on the one hand or exploiting others on the other. People have many things they might be doing at any given moment besides those two activities. In short, it seems from the opening vignette that the authors not only concede but require that it be true that grieving carries very big opportunity costs, even if one is a prosocial sort of person. Yet their argument also requires that the opportunity costs of grieving people to be small, at least relative to non-grieving people.”

This is an excellent point. The argument is that the grief signal must be costly because otherwise dissemblers would deceive others by displaying it. Upon the other hand, there must be a differential cost between those who grieve intensively and those who do not because no one would grieve if it didn’t benefit him or her in Darwinian terms (i.e., inclusive fitness). So what gives?

I think one possibility, one that is addressed in the article, is that the rewards for grieving are larger for a person who is prone to forming strong commitments than for a person who is not. And this is an important part of the of the cost/benefit analysis of signaling. A relatively commitment-free person, a person who cultivates a number of superficial associations, is simply not rewarded as much as a person who forms intense commitments by the addition of strong social bond. If this seems a bit muddy, consider an analogy. Researchers have proposed that men engage in different mating strategies. For simplicity, we can dichotomize these: short term and long term. Now, let us consider a short-term man (Steve) and a long-term man (Bill). Suppose that Steve and Bill both zero in on an attractive woman. They would both like to sleep with her. However, let us suppose that she is particularly fastidious and requires significant investment before sleeping with a man. Both men could, of course, attempt to woo her with expensive dinners, elegant poems, and exquisite displays of investment. But the cost/benefit structure of such displays is different for the two men.

Steve desires a few sexual encounters, not a long-term relationship; Bill desires a long-term relationship. Therefore, if Steve accomplishes his goal, he will obtain access to a few sexual episodes. This is certainly a positive evolutionary outcome, but it is not so important to Steve as is a long-term relationship to Bill. Presumably, Steve could procure sexual access somewhere else and without extreme costs. This means that, ceteris paribus, Bill is more likely to emit displays of investment. And this is, in fact, why women use such a vetting system: it deters those who do not actually intend on forming a stable pair bond.

It seems plausible that grief could operate in a similar manner. So, take two men: John and Dilbert. Now suppose that John is a social butterfly who flits from person to person and group to group, making the most of a high volume of low commitment friendships and group bonds. Dilbert, upon the other hand, practices a high commitment social strategy. Once he bonds with a group, he remains loyal until the bitter end. Same with individuals. John would probably avoid groups that require large initial investments or costs because his strategy is best advanced by seeking low cost social opportunities, whereas Dilbert might be attracted to them. Grief might function as a costly initiation practice, deterring people like John from extracting the benefits of a close-knit, highly committed group.

In fact, this can be quantified, and the math shows that it could work. Please excuse the ridiculously crude nature of this equation. The basic point is simply that the math works. So, suppose that grief costs 1 unit of inclusive fitness (RS). And suppose that the rewards for grief are different for a person with a propensity for forming strong social bonds (Dilbert) than for a person who lacks such a propensity (John) such that the reward to Dilbert = 1.1 RS and the reward for John = .7. Both receive rewards for their displays, but the rewards are differentially rewarding. In this (very simple, crude model), Dilbert achieves a .1 RS gain for the signal and John loses .3 RS for the signal.

Of course, as I said, this is remarkably crude; the real world is much more complicated. The costs/benefits would most likely be distributed across a continuum (i.e., from low grief to high grief, low benefit to high benefit). This also doesn’t consider the signaling component from a group perspective. Nevertheless, the important point is that the math could work. This, of course, doesn’t mean that it does. That is an empirical question, and I am hopeful that future research is conducted that either refutes or supports the theory.

Kurzban’s second objection is that the theory relies on signaling a “type.” That is, according to the theory, a griever is signaling that he or she is prosocial. Kurzban points out, quite correctly, that underlying propensities for prosociality do not necessarily cross relationship domains. In other words, a person might be a very cooperative and committed husband, but an irascible and uncooperative friend. Although I think the general point is correct, I do not believe that it is fatal to the signaling theory. It is a fair assumption that people who commit and cooperate with one person are more likely to commit and cooperate with another person. I suspect that this is relatively domain general, although there are some egregious counter examples (e.g., Bonnie and Clyde—although, contrary to popular understanding, Bonnie and Clyde weren’t loners, and they may have been quite loyal to their fellow gang members). We do, for example, use small snippets of behaviors to predict future behaviors, and we do so because such small snippets are, at the very least, somewhat informative. Likewise, we use a person’s behavior in one relationship as a gauge of his or her behavior in another relationship.

Again, though, this is an empirical question. And it does raise intriguing questions. For example, would women be more affected by a husband’s grief for a deceased wife than men? Would men be more affected by a man’s grief for a fallen group member than women? Who would respond more to grief displays about children, brothers, sisters, or other kin? At any rate, the problems forwarded by Kurzban are important and thought provoking—and I appreciate the discussion.

Last, before concluding, I want to note that there are several reasonable proposals about the evolutionary function of grief. I suspect that the human grief response was shaped by multiple selective forces, so there isn’t any one single function of grief. Too often, we as evolutionary thinkers attempt to ascertain the reason or the function for a particular trait as if reality were a multiple-choice test with only one correct answer. Randolph Nesse, Tooby and Cosmides, John Archer, and others have forwarded compelling theories about the function (s) of grief. The signaling theory of grief does not argue that any of these theories are entirely incorrect. It is rather unlikely that we will discover the special selective force that led to our species’ incredible intelligence because there isn’t one; similarly, it is unlikely that we will discover the single selective force that shaped the human grief response because it doesn’t exist. Instead of searching for some absolute answer, some absolute perspective on such puzzles, we should look through multiple windows. Initially, this might make our view more fragmented, but ultimately it will lead to a more comprehensive understanding.

If the signaling theory is part of the story about grief, a griever’s laments may not be ineffectual communications to the dead; instead, they may be powerful signals to the living.



Kurzban, R. (2014). Good Grief.



Winegard, B. M., Reynolds, T., Baumesiter, R. F., Winegard, B., & Maner, J. K. (in press). Grief Functions as an Honest Indicator of CommitmentPersonality and Social Psychology Review.




Posted in Uncategorized | Comments Off on Let the dead bury the dead?