Interesting Science Picture: Part II

Figure 1. Melanosomes in the feathers of the male zebra finch. (a) Optical photographs of lateral (top) and ventral views of the specimen sampled. (b, c) Optical photographs of breast feather (b) and flank feather (c). (d-i) SEM images of melanosomes inside barbs and barbules. (d-e) Eumelanosomes (at arrows in (e) in the barb of a breast feather. (f-g) Phaeomelanosomes (at arrows in g) in the barb of a flank feather. (h-i) Barbule of a flank feather in which the superficial layer has peeled away to expose aligned phaeomelanosomes (at arrows in i). Abbreviations: b, barb; bl, barbules; s, superficial layer. Scale bars: a, 10 mm; b, 5 mm; c, 5 mm; d, 100 µm; e, 5 µm; f, 30 µm; g, 3 µm; h, 10 µm; I, 2 µm.

From the supplementary material to this article:

Fucheng Zhang, Stuart L. Kearns, Patrick J. Orr, Michael J. Benton, Zhonghe Zhou, Diane Johnson, Xing Xu, and Xiaolin Wang.
Fossilized melanosomes and the colour of Cretaceous dinosaurs and birds.

Primate Brain Evolution And The Hobbit

BMC Biology has a 64 page paper on brain evolution in primates. The paper focuses on Homo floresiensis and concludes that (from the abstract):

Our results confirm that brain expansion began early in primate evolution and show that increases occurred in all major clades. Only in terms of an increase in absolute mass does the human lineage appear particularly striking, with both the rate of proportional change in mass and relative brain size having episodes of greater expansion elsewhere on the primate phylogeny. However, decreases in brain mass also occurred along branches in all major clades, and we conclude that, while selection has acted to enlarge primate brains, in some lineages this trend has been reversed. Further analyses of the phylogenetic position of Homo floresiensis and better body mass estimates are required to confirm the plausibility of the evolution of its small brain mass. We find that for our dataset the Bayesian analysis for ancestral state reconstruction is least affected by inclusion of fossil data suggesting that this approach might be preferable for future studies on other taxa with a poor fossil record.

I haven’t read the entire thing yet and will have more to say when I have…

Four Stone Hearth Volume #85 Is Up!

Check out the best that anthropology has to off at A Very Remote Period Indeed.

Herskovits At The Heart Of Blackness: A Review

Melville Herskovits was one of a number of Boasian anthropologists. Like Kroeber, and a plethora of Boas’ other students, Herskovits founded an anthropology department. He wrote economic anthropology and cultural relativism. He is not really mentioned in theoretical overviews (such as in High Points in Anthropology) and I hardly ever heard him in mentioned in anthropology classes. Where his name did come up was in African-American Studies classes. This is largely due to his classic book The Myth of the Negro Past. Prior to Herskovits, there seemed to be this notion that African-Americans were a people without a cultural past or rather that there was a clean cultural break, caused by the Middle Passage, between Africa and African-Americans. The voyage across the Middle Passage combined with the horrid effects of slavery were enough, it was felt, to completely eradicate any trace of African culture from the African-American. Of course, the African culture itself was deemed to be static and unchanging and the documentary illustrates this, to great effect, using clips from old cartoons and Tarzan movies.

Herskovits, although not the first, disagreed and argued that there was cultural continuity between the cultures of African and the far flung members of the African Diaspora. He based this, in a large part, on fieldwork in Africa, South America, and the West Indies. Which brings me to an upcoming episode of the PBS Series Independent Lens. Continue reading

PhyloCode: Love It? Hate It? Totally Indifferent To It

Lately, I’ve been getting into the literature on taxonomy and systematics. At this point I don’t know enough to say much about it one way or the other. I am interested in what you, my knowledgeable readers, think about phylocode. I’m particulary interested in what impact it will have on the taxonomy of primates and hominoids in particular – but you all don’t have to address that….

Time For A Leadership Change In The Democratic Party

At least that is what this says to me:

The worst is that I can’t help but feel like the main emotion people in the caucus are feeling is relief at this turn of events. Now they have a ready excuse for not getting anything done. While I always thought we had the better ideas but the weaker messaging, it feels like somewhere along the line Members internalized a belief that we actually have weaker ideas. They’re afraid to actually implement them and face the judgement of the voters. That’s the scariest dynamic and what makes me think this will all come crashing down around us in November.

Sorting the butchered from the boiled: An Interesting Picture Of Collagen

Fig. 4. Shows TEM images which are representative of the collagen from the ‘cooked’ (group A) and ‘uncooked’ (group B) bones. In group A (images a, b and c) the collagen was mainly observed as long intact fibrils with frayed ends and beaded regions. In group B (images d, e and f) the collagen was considerably more damaged. Whilst some beaded fibrils were also present in this set of bones (f) the majority of the fibrils were observed as short fragments with frayed ends i.e. Dumbbells (e) or as gelatinous clumps (d). The scale bars are 500 nm.

From: here


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