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[T]wo subjects which moved my Father perhaps more deeply than any others were cruelty to animals & slavery – his detestation of both was intense, and his indignation was overwhelming in case of any levity or want of feeling on these matters.  – William Darwin

The trick to finishing books this year is getting up early, apparently.  I managed to get through the last four chapters of Darwin’s Sacred Cause this weekend while the baby slept. In the process, I’ve had to come to terms with  the disquieting beginnings of my own discipline and the bloody and violent antecedents of the town I’ve called home for the past dozen years.

Charles Darwin and Abraham Lincoln share a birthday, but they also share a tumultuous period in history. I’ve always been struck by the realization that Origin of Species was published just a few short years before the Civil War. After reading Darwin’s Sacred Cause, I get the idea that it was not coincidental.  Yes, Darwin sat on his big idea for 20 years, publishing travel journals, works on geology, and a four-volume monograph on barnacles. Why barnacles?  First, to document the amount of variation present in species, which natural selection requires to operate; and second, to establish himself as a knowledgeable naturalist in the eyes of the Royal Society, and provide the credentials needed to discuss his theory. In addition, describing the complete lineage of these marine arthropods provided an example of common descent. Barnacles were a proxy for a much more controversial topic – human variation.

Not science

Human variation is what I study as a biological (or physical) anthropologist. Physical anthropology has its roots, at least in part according to the authors, in phrenology. That’s the pseudo-science of determining temperament from the shape of the skull.  Not surprisingly, given that phrenology developed in Europe, Europeans were said to have the most refined skulls, and phrenological findings were used to justify slavery, something Darwin’s entire family was against.  Darwin would not have been impressed with the physical anthropologists of his day, especially in America, where differences in skull morphology were seen as “proof” of a polygenic origin of humans. According to the polygenists, each human “race” had its own pair of progenitors and were separately created, an idea used to justify all sorts of atrocities, since non-Europeans were seen as less than human. Darwin held the monogenist view, and saw all peoples as descended from a common ancestor, meaning they were all worthy of being treated with dignity and respect, and slavery was unjustified.  Actually, he took it farther than that, and saw a common ancestor for all living things.

It is absurd to talk of one animal being higher than another.–We consider those, where the cerebral structure/intellectual faculties most developed, as highest.–A bee doubtless would when the instincts were. – Charles Darwin

He spent a number of years studying pigeons, just to demonstrate that all the fancy breeds (“races”) descended from a common ancestor. Another proxy for human variation.

Darwin’s Pigeons – from Variation in Animals and Plants under Domestication (1868), with the common ancestor, the rock dove, in the center.

The tension between these two worldviews played out in my hometown, before the Civil War even started. In 1856, Sheriff Samuel Jones led a pro-slavery posse into Lawrence, Kansas, which had been established by abolitionist settlers two years before, sacked the town, burned the Free State Hotel, smashed the presses, and killed an antislavery supporter.

The ruins of the Free State Hotel

Darwin’s mentor and friend, geologist Charles Lyell, who encouraged him to publish his ideas on natural selection, was a Southern sympathizer. The Anthropological Society of London was founded in 1863, in the midst of the Civil War, with three Confederate agents on the council, whose sole purpose was to push a pro-slavery agenda.

Plaque on the site of the present-day Eldridge Hotel, 8th and Massachusetts, Lawrence, Kansas.

Plaque marking the site of the Free State Hotel, downtown Lawrence.

That’s what Darwin was up against.  Not just other naturalists, but Victorian society. No wonder he waited two decades to publish.

My discipline has come a long way since Darwin’s day.  The American Anthropological Association’s “Statement on Race and Intelligence” states in part:

WHEREAS all human beings are members of one species, Homo sapiens, and

WHEREAS, differentiating species into biologically defined “races” has proven meaningless and unscientific as a way of explaining variation (whether in intelligence or other traits),

THEREFORE, the American Anthropological Association urges the academy, our political leaders and our communities to affirm, without distraction by mistaken claims of racially determined intelligence, the common stake in assuring equal opportunity, in respecting diversity and in securing a harmonious quality of life for all people.

And the American Association of Physical Anthropologists has their own “Statement on Biological Aspects of Race,” which says:

Physical, cultural and social environments influence the behavioral differences among individuals in society. Although heredity influences the behavioral variability of individuals within a given population, it does not affect the ability of any such population to function in a given social setting. The genetic capacity for intellectual development is one of the biological traits of our species essential for its survival. This genetic capacity is known to differ among individuals. The peoples of the world today appear to possess equal biological potential for assimilating any human culture. Racist political doctrines find no foundation in scientific knowledge concerning modern or past human populations.

Image Credits:

Ryan Somma’s flickr stream

Wikimedia Commons

Dr. Steven M. Carr’s website

ResearchBlogging.orgAs reported in the New York Times, the cover article of Nature this week describes the sequencing of a Paleo-Eskimo genome from Greenland.  This is the first ancient sequence from the New World, and is important for a number of reasons:

  • The sequence analysis was conducted from a sample of human hair that was recovered from permafrost, and the DNA was recovered from the hair shaft, not the root. This opens a whole new avenue of paleogenomic research.
  • SNP analysis shows that the hair belonged to an individual who carried a number of traits frequently found in modern Asian populations, including shovel-shaped incisors and dry ear wax.
  • 85-87% of the genome was sequenced – phenomenal coverage given the age of the sample.

Chukchi women (seated front right), circa 1906

  • Population genetic analysis (principle component analysis of genetic distances) revealed the closest relationship between the Greenland genome and the Chukchi, a population in northern Siberia, suggesting a recent migration (in the last ~5,000 years) from Siberia across the Arctic to Greenland. This would be in addition to the three migrations (Amerind, Na-Dene, and Eskimo-Aleut) traditionally hypothesized for the peopling of the New World.

Rasmussen et al. (2010) Figure 3b. PCA of populations - Saqqaq genome indicated by star.

I was disappointed that more North American samples weren’t included in the analysis.  With the exception of populations from West and East Greenland, Na-Dene in western Canada, and Aleuts, the only other Native American groups are from Central and South America. But overall, this study demonstrates how ancient DNA analysis can help answer historical questions.

Disclaimer: One of the co-authors (Michael Crawford) was my graduate mentor. Which, for me, makes this study even more awesome.

Image credit: Wikimedia Commons

Rasmussen, M., Li, Y., Lindgreen, S., Pedersen, J., Albrechtsen, A., Moltke, I., Metspalu, M., Metspalu, E., Kivisild, T., Gupta, R., Bertalan, M., Nielsen, K., Gilbert, M., Wang, Y., Raghavan, M., Campos, P., Kamp, H., Wilson, A., Gledhill, A., Tridico, S., Bunce, M., Lorenzen, E., Binladen, J., Guo, X., Zhao, J., Zhang, X., Zhang, H., Li, Z., Chen, M., Orlando, L., Kristiansen, K., Bak, M., Tommerup, N., Bendixen, C., Pierre, T., Grønnow, B., Meldgaard, M., Andreasen, C., Fedorova, S., Osipova, L., Higham, T., Ramsey, C., Hansen, T., Nielsen, F., Crawford, M., Brunak, S., Sicheritz-Pontén, T., Villems, R., Nielsen, R., Krogh, A., Wang, J., & Willerslev, E. (2010). Ancient human genome sequence of an extinct Palaeo-Eskimo Nature, 463 (7282), 757-762 DOI: 10.1038/nature08835

A subject that’s been on my mind quite a bit this week, and coincidentally, several related things have popped up on my radar. First, a video from SciVee, intended for high school girls who might be considering a career in science.

The best advice? Just do it. If that’s what your passion is, go for it.

When I was a very little girl, I remember my father coming to pick me up from daycare one day. I was in tears, and when he asked me what was wrong, I told him that my teacher had asked all of us to tell what we wanted to be when we grew up. When I said that I wanted to be an astronaut, my teacher said I couldn’t because I was a girl (this was pre-Sally Ride). My father confronted the teacher, and informed her that his daughter could be anything she wanted to be. Knowing that a trusted adult believed in me gave me the confidence to pursue my dreams. Just one of the reasons I adore my dad.

Sally Ride - First American Woman in Space

My high school biology class turned my attention from outer space to DNA. After those Punnett squares, I never looked back. But that confidence in my abilities never wavered.

***

Also, the National Postdoctoral Association posted their 6 Core Competencies for postdocs:

to offer guidance to individual postdoctoral scholars who must seek out relevant training experiences, in collaboration with mentors, institutions, and other advisors who provide this training…These competencies are meant to serve primarily as: (1) a basis for self-evaluation by postdoctoral scholars and (2) a basis for developing training opportunities that can be evaluated by mentors, institutions, and other advisors.

Postdocs can use the checklist to identify areas for future development, and as a springboard for discussion with their mentors.

***

Finally, an article from Science Careers – Reaching gender equity in science: The importance of role models and mentors.

One of the factors that has inspired more women to pursue scientific careers has been having examples of successful women who have done the same.

I feel very fortunate to have a team of mentors, one of whom is a very prolific and successful scientist, woman, and mother.  When I started graduate school, my concern was mostly with the academics. Completing my courses, making sure I had enough time in the lab to get my research done, writing.  I hadn’t really considered the importance of mentoring in establishing my career. I can see now that it is essential, and especially beneficial to have a group of senior researchers interested in your professional development, even if their advice seems sometimes contradictory.  And while this may not be the case for some postdocs, I know that they all genuinely have my best interests in mind.  I’m beginning to see my graduate training, and by extension my postdoc, as an apprenticeship.  A position where I learn how to be a scientist, with all the core competencies that entails.

By Dai Cooper, via my grad student listserv.

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