The American Association of Physical Anthropologists (AAPA) had its 84th annual meeting last week in St. Louis, Missouri. The AAPA is the world’s leading professional organization for physical anthropologists. Its annual meetings draw 1,000+ scientists and students.
I followed most of the event on twitter and really enjoyed this experience, thanks to 20+ attendees who were tweeting live the key moments of the meetings. Therefore I decided to add another small contribution by sorting and posting the 101 tweets I collected during the event.
Thank you very much @HermanPontzer @johnhawks @HumanOrigins @APV2600 @Fidydvm @thewildniche @GPOrangutans @Paleophile @AAAGenetics @Anthro_Austin @mitoPR @LittleMsFossil @AlesiaAlesiaki @lancegravlee @darcy_shapiro @osteo_jo @DrKillgrove @rgairnelson @lancegravlee @ZThrockmorton @LoVUMass — Sorry if I’m missing someone – and happy to receive any correction or further contribution!
The post structure is: [ Session | Presenter: Summary ]
Energetics in Human and Non-Human Primate Evolution: Moving from Theory to Empirical Tests.
Amy Bauernfeind: using futuristic methods, shows that human brains use more energy, differently, than chimps.
Chris Kuzawa: brain growth velocity is in direct inverse relation to body growth velocity in children.
Paleoanthropology: Early hominin evolution
Carol Ward: New A. anamensis fossils support earlier interpretations of different morphology in that species vs. A. afarensis.
Adam Sylvester: A. sediba distal femur shape is unique: similar to other australopiths in some ways but modern humans in other ways.
Sandra Mathews: our shoulder mobility, good for tool use, bears a cost: shoulder pain & injuries – some of which increase w/ age.
- At some point in our evolutionary history our hands were more strongly selected for manipulation than locomotion.
- Did human hand proportions evolve for making tools? No b/c proportions largely primitive, well predating stone tools.
Claire Terhune: large differences in two A. sediba mandibles, but not larger than other apes and not b/c ontogenetic shape variation.
N. Roach: a lot of changes in our upper bodies around time of earliest stone toolmaking – are they related?
Human Biology: Reproduction, health and disease
Models suggest that animals did not evolve to provide care to kin affected with highly transmissible and lethal diseases.
C. Warriner: direct evidence of milk consumption from ancient human dental calculus (Neolithic & younger).
Filling the Geographic Gaps in the Human Evolutionary Story
Michael Petraglia: new findings of early human dispersal through Arabian peninsula:
- (non-coastal) Arabian peninsula ignored in evolutionary dispersal scenarios. In part because of lack of fossils.
- Arabian peninsula is a key bridge between Africa and Eurasia. Lots of climate change in past w evol, implications.
- Important under discussed aspect is lineage level extinction (yes!). Good reason to study understudied areas.
- Remote sensing reveals lots of paleo rivers in Arabia, lots of potential habitat variability.
- Lots of documented Acheulean sites throughout Saudi Arabia. Typically focused on river corridors.
- Acheulean sites particularly at intersection of paleo rivers and andesite raw material sources.
- Starting to find associated water dependent fauna fossil material at Acheulean time period sites. Area was a mosaic.
- We don’t know what happens when climate turns dry. Extinction? Refugia? Dispersal? Fauna do suggest extinction happens.
Knut Bretzke: discontinuities in dry times and lithic variation suggestions pulses of occupation associated w humidity.
Sireen El Zaatari:
- Paleolithic of Lebanon. After extensive mid20th century work, Lebanese civil war ended work, which has yet to recover.
- Almost everything we known of Lebanese Paleolithic is from before 1970.
- LKH1 is Neandertal tooth associated w initial UP. Contemporaneous w possible Uluzzian.
- Apidima 2 is a great fossil skull, but inaccessible. Possible affinity w Saccopastore.
Mirjana Roksandic: Mala Balanica, Serbia, mid Pleistocene hominin mandible BH-1. Not Neandertal-like in its morphology.
- In marginal environments of N Asia, increased sensitivity to climatic fluctuation n local extinction.
- Ust’-ishim femoral DNA appears to leave no living descendants. More evidence of local extinction of lineages.
- Genetics of Ust’-ishim and Tianyuan suggest population discontinuity between GIS 12 and 8. Past demography not simple.
- Azokh Cave (~300ka) in Armenian southern Caucasus. Important link region.
- Neandertal upper M1 found in unit 2 of Azokh Cave.
- Biogeographic model for understanding occupation of Central Asia, given known paleogenetic diversity.
- Did hominins persist across glacial interglacial periods? If yes, r sites aggregated?
- Hominins persist across climatic fluctuations, and correlate w bioclim variables (temp seasonality, max cold).
- Model predicts big difs between steppe n foothill environments of C Asia. These difs r more extreme during interglacials.
- Gap in Chinese hominin fossil record between 100-40ka. Guangxi record says no.
- Sanxieshan molar possible erectus near erectus-archaic homo interface in China? ~300-400 ka.
- Pa Hang excavations in Laos. Fossils of at least three individuals (~40-65ka) No associated archaeology.
- Tam Pa Ling 2 mandible strikingly small, but w robust corpus. Corpus looks like archaic homo, but w a prominent chin.
Robert O’Malley: high ranking female chimpanzees eat more meat, low ranking ones ramp up consumption when pregnant.
- All apes make nests; hominins probably had same manual dexterity & could weave vegetation into a sling.
- How do orangutans carry infants? And what does this mean for human evolution?
Paleoanthropology: Genus Homo
- Dmanisi skulls indicate selection on morphology for migration out of Africa.
- Most neurocranial diversity in earlier Homo skulls was the result of genetic drift, not selection.
- Found close to 100 hominin footprints at 8 sites at Koobi Fora, Kenya at ~1.5Ma.
- Doing systematic sampling in 2014 found 20 more sites w/ footprints (hominin and non-hominin).
- Looks like 1.5 Ma hominins were favoring near-water environment, traveling in groups, and were of modern body size.
Kevin Hatala: modern human and 1.5Ma Ileret footprints indicate similar locomotion, and very different from 3.7Ma Laetoli footprints.
Carol Ward: Nearly complete very large 1.5Ma hominin (early Homo) radius from Koobi Fora, bigger than nearly all modern humans.
Whitney Reiner: New 15-60 thousand year old calvarium and a few teeth from Olduvai Gorge, Tanzania, is generally African modern human-like.
Karen Baab: Did LB-1 (H. floresiensis) have Down syndrome? Comparisons w/ many features of modern humans say no.
The future of the Middle Pleistocene: New evidence from the Sima de los Huesos (Sierra de Atapuerca, Spain)
- Sima de los Huesos (Spain) has the largest collection of Middle Pleistocene hominins in the world: >200 individuals!
- The site is in Atapuerca, Spain, dated to 430Ka. >6500 human (Neanderthal?) remains so far.
- How did the nearly complete skeletons get to Sima de los Huesos? Transport? No. Carnivores? No. Accidents? No. Transport of Sima de los Huesos hominins was not geological/natural, but by the hominins themselves.
- The Sima de los Huesos skeletons were intentionally transported (by hominins) & one suffered blunt force trauma.
- Homo heidelbergensis may not fit into human ancestry as many currently suggest.
- Mauer mandible anatomy is highly derived -> unique clade too specialized to be ancestor of modern humans or Neandertals.
María Martinón (in absentia):
- The Sima de Los Huesos teeth are more Neanderthal than Neanderthals *audience laughs*
- Shape analysis of Sima de Los Huesos teeth may be more informative than metric measurements.
- Sima de los Huesos teeth features unique -> one population among many in Middle Paleolithic Europe.
Asier Gomez-Olivencia: Vetebrae & thorax of Sima de los Huesos hominins similar to Neanderthals but don’t show all features (mosaic).
- Most complete pelvis from the fossil record is an older male from Sima de los Huesos nicknamed «Elvis».
- Mosaic but robust morphology of Sima de los Huesos pelves largely primitive for the genus Homo.
Adrián Pablos: Feet morphology from one (prob male) individual suggests balanced bipedalism in Sima de los Huesos hominins.
José Miguel Carretero: SH hominins more robust and a bit taller than Neanderthals but with limb proportions similar to AMH.
Juan Luis Arsuaga:
- Large Sima de los Huesos collection is instrumental for understanding ancient hominin variation.
- Neandertal traits emerged in Europe much earlier than modern human traits emerged in Africa.
- Type specimens must be informative, otherwise species designation is invalid, this is a problem for H heidelbergensis.
- Taxonomy has rules, with all due respect, and the first rule is gtat the type specimen must be informative.
- If only! Realistically laws of taxonomy mean it is the first named- sufficiently informative or not.
- Homo heidelbergensis was named in 1908 but the Mauer mandible is not sufficient for comparison to other samples.
- Homo heidelbergensis — in reality this species should have stayed dead instead of being resurrected in 1980s.
- Others predicted that when a large Middle Pleistocene sample was found, it would encompass the variation of the known record.
- What we found instead in the Sima sample is that the skulls are like clones, very little variation in features.
- Occipital bone of Sima de los Huesos specimens is unique-not Neanderthal. It’s a different character state.
- Sima skulls most similar to Swanscombe skull in occipital, but differing facial morphology.
- If Sima de los Huesos and Ceprano are the same age, then the anagenetic pattern in Europe is killed, must be branching evolution.
- Very much a branching pattern of Pleistocene hominins in Europe-lots of change, regional variation.
- Branching evol pattern in response to glaciers in Europe is the games of thrones hypothesis. Winter is coming!
Rethinking Racial Health Disparities: The genetic anthropologist’s contribution to debates over health inequalities
- There is a gap b/w our teaching of the science of human variation and what this truly means for our student’s lives.
- Teaching human bio diversity through focus on sports. Lessons more likely to stick because relates to everyday life.
“There is a huge gap between social change and political action» Ferguson.
Rick Kittles: As we move towards personalized medicine, we can’t stop at race as a proxy for biological differences.
Britanny Hollister: Many large studies fail to control for SES causing spurious associations between health outcomes and ancestry.
Jeffrey Long: The majority of diversity of old, groups are not usually monophylitic, group specific alleles are rare outside Africa.
«Race is not a biological reality. But it has huge biological consequences.»
Paleoanthropology: Hominins, taxonomy and taphonomy
Martin Haeusler: Painful-looking prox femur osteoarthritis in Au. Africanus.
«As scientists, we are often trained to focus on the data. It’s time to think beyond.»
«We tend to think about the science and stick to the science. We need to think beyond our lab doors.»
- Humans are polymorphic for presence of third molar
- 1/4 people experience third molar agenesis (according to meta study).
- Females 14% more likely to experience agenesis.
Skeletal Biology: Demography and Forensic Anthropology
Amanda Kittoe: Can sexual dimorphism be expressed differently across human populations? I’d say yes, very much so. Especially metrically.
Caroline VanSickle: Can the sex of hominin pelvic fossils be assessed using methods developed for recent humans? No.
- Comparing face to the body, which is better for ID?
- Using 8 face traits, probability of finding exact match is 1 in 1 trillion. Body = 1 in one quadrillion.
- If both face & body covered by clothing at crime scene, body is better; less influenced by clothing than face is by cover.
- Face and body ID techniques are both as good as DNA, but easier and cheaper.