Wednesday, May 20, 2009

Moving to Wordpress

After leaving ScienceBlogs one of my goals was to find a place where I could combine my posts from Blogger and ScienceBlogs. After messing around with Blogger for about a week I have decided to move to Wordpress - which has a wide variety of importing tools. Something lacking in blogger. You can find me in my new, and hopefully permanent home at Afarensis: Anthropology, Evolution, and Science. Please adjust your links accordingly. Where remodeling will commence anew!

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Tuesday, May 19, 2009

Were Neandertals Cannibalized By Anatomically Modern Humans?

And can you really call it cannibalism if they are not Homo sapiens neanderthalensis? The lemur/adapid/anthropoid paper is not the only anthropology paper out this week, nor is it the only one that has been the subject of over exuberant reporting. The gist of the story is that the jaw below contains cutmarks:

The jaw may also be a Neanderthal jaw associated with an Aurignacian site. I don't have much to say about it it other than the few articles I saw played up the cannibalism. Really, I just wanted an excuse to post the picture, but if you want to know more you can go read Hawks. I'll have a post up on the adapid story sometime in the next couple of days.

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Sunday, May 17, 2009

Corporate America and Wage Theft

Kim Bobo has an interesting discussion of the subject. Having worked in corporate America all my working life, I particularly liked this part:

The worker who steals from the employer is fired and may go to jail. The consumer who shoplifts goes to jail. The employer who steals wages will probably not get caught. In the last decade, if an employer were caught stealing wages, the employer might have to pay back the wages, but probably not all the wages actually owed. Hopefully, the consequences for employers who steal wages will be more significant under the leadership of Secretary of Labor Hilda Solis.

This part is good as well:

On the other hand, there does seem to be a culture permeating many companies that suggests that the lowest wage you can get away with is the best wage. And given the pervasiveness of wage theft, we need some huge shifts - not only in wage enforcement but business culture.

At any rate, go read the rest...

There is also this

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Thursday, May 14, 2009

Stupid Creationist Quote of the Week

Today we have comments by two commenters at UD.

First up is a commenter named Barb. Barb left a rather lengthy comment talking about Lucy. The part that earned her a "stupid creationist quote" award is this:

The paucity of fossil evidence makes knowing all of human evolutionary history impossible. The best evidence for Lucy came, not from bones or teeth, but from footprints.

There are over 250 specimens referable to Australopithecus afarensis - Lucy being the most widely known example:

AL288-1 Most of the specimens of A. afarensis were discovered in the 1970's, but a significant number have been discovered in the years since. Our knowledge of A. afarensis does not come from the few papers written about the Laetoli footprints. Our knowledge of A. afarensis comes from a thorough study of their anatomy and by comparing these specimens to those of monkeys, apes, and hominins (including humans). At this point there are hundreds of scientific studies, consequently, anyone who claims that knowledge of "Lucy" comes mainly from footprints quite simply does not know what they are talking about. Barb then claims that all the fossils pertaining to human evolution can fit into a single coffin. She is corrected on this by a later commenter, who points to some fossils, then Barry Arrington jumps into the fray:

eintown, thank you for making Barb’s point even more forcefully. It shows what we already know to be the case. The fossils in question are very fragmentary (not complete skeletons as you implied), and altogether they could easily fit in an average sized coffin
. I have addressed this idiotic argument in a previous post so I will quote from that:

At Omo over 500 specimens have been found representing gracile and robust australopithicines and early homo. At Sterkfontein over 600 specimens representing over 50 individuals from Australopithecus africanus, A. robustus and Homo habilis. At Makapansgat over 30 specimens representing approximately 12 individuals from A. robustus and H. erectus. At Hadar over 250 specimens representing approximately 35 individuals from A. afarensis. At Atapuerca/Gran Dolina 100 specimens from 6 individuals. At Atapuerca/Sima delos Huesos 28 individuals. At Predmosti 29 individuals. At Dolni Vestonce 35 individuals. At Krapina 800 specimens representing over 80 indivuals. At Vindija 80 specimens. At Skhul 10 individuals. At Shanidar 9 individuals. Whats missing from the list I just presented are sites such as Olduvai Gorge and Sangiran, among others. The amount of diversity in terms of morphology in the above list is certainly adequate to characterize the full range of variation for most of the species we are familiar with.


Some of the other sites I didn't give figures for are Koobi Fora, Modjerko, Zhoukoudian (both the H. erectus site and the upper cave), Abri Pataud, Jebel Irhoud, (three fairly complete skulls, of which two are adult and one is a juvenile), Allia Bay, Ambrona, Arago, Baringo, Blombos, Bodo, Dali, Maba, Dmanisi, Drimolen, Florisbad, Hexian, Lake Mungo, Petralona, etc, the list goes on and on. The Catalogue of Fossil Hominids put out by the British Natural History Museum in 1976 listed over 3900 fossils. I've heard recent estimates in the 10,000 range.

Finally some other sites where hominins of one sort or another have been found:

Swanscombe, Steinheim, Nariokotome, Ndutu, Olorgesailie, Konso-Gardula (in the Middle Awash), Daka, Ngandong, Florisbad, Die Kelders Cave, Equus Cave, Border Cave, Klasies River Mouth, Herto, Aduma, Ngaloba, Eliye Springs, Rabat, Dar-es-Soltane, Mugharet el Aliya, Zouhra, Engis, Forbes Quarry, Neander Valley, Spy, Ehringsdorf, Le Moustier, La Chapelle-aux-Saints, La Ferrassie, La Quina, Mladec, Brno, Ochoz, Sipka, Cro Magnon, Laetioli, Kanapoi, Mauer, Lothagam, Lukenio, Ngororaa, Tabarin, Bouri, Peninj, Chesowanja, Konso, Lomekwi, Sali, Trinil, Gongwangling, Lantian, Yuanmou, Jian Shi, Yiyuan, Yunxian, Boxgrove, Bilzingsleben, Ceprano, Reilingen, Biache, Montmaurin, Saccopatore, Kabwe, Saldanha, Eyasi, St. Cesaire, Zuttiyeh, Wajak, Niah Cave, Kow Swamp, Tandou, just to name a few more...Oh, I almost forgot Olduvai Gorge and Flores.

The specimens found at these sites range from fragments (which can be informative depending on the morphology that they preserve) to entire bones to partial or complete skeletons. We have already seen Lucy, here are some others.

part of the more complete "Little Foot" skelton - may be A. africanus

Homo habilis OH-62

H. erectus KNM-WT 15000

Neanderthal Shanidar 4 and 6

Neanderthal Shanidar 3

Neanderthal Shanidar 1

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Tuesday, May 12, 2009

Do Deep Sea Fish Have Good Hearing?

An interesting article over at National Geographic looks at that question:

Roughly 90 percent of the ocean is completely dark, beyond the reach of the sun's rays.

The researchers wondered if the fish had evolved to have sharper hearing, which might help them catch prey, find mates, or elude predators in the darkness.

The researchers were looking at fish that lived in waters as deep as 1.6 miles. What they found was interesting:

The inner ear (pictured) of a blue antimora (inset) is exceptionally rigid—a feature never before seen in a deep-sea fish, according to a study to be presented in May 2009.
Photograph courtesy Xiaohong Deng et al.; inset photograph courtesy NOAA

A couple of things stand out in the National Geographic article. First, the ears were compared to those of surface dwelling fish and were found to have long rods attached to their ototliths:

"We do not quite know what [the stalks'] function is yet," said study co-author Xiaohong Deng, a marine biologist at the University of Maryland.

But Deng suspects these stalks allow the otoliths to register sounds that would otherwise be too faint to hear.

The ridgehead ears' also had very long hair bundles—features also seen in the ears of shallow-water species known to have great hearing, such as the pinecone soldierfish and clown knife fish. The bundles may enhance the fish's sensitivity to sound and to their own head motion, which would improve the fish equivalent of balance, Deng said.

Second, a second species had rigid inner ears similar to that found in bluefin tuna. The close proximity of the swim bladder - an organ that controls buoyancy and amplifies sound - strengthens the suggestion. What this says to me is that evolution has found multiple ways of dealing with darkness. It also indicates that the affects of selection on the swim bladder, or for better hearing, are likely to have unintended consequences...

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Monday, May 11, 2009

Adapidae, Omomyidae, and Anthropoid Origins: Updated

In a previous post I discussed competing views about adapids and omomyids. In that post I said:

There is a further complication. In both 2 and 3 above tarsiers are grouped with anthropoids and adapids are grouped with lemurs and lorises. The problem is adapids share quite a few traits with anthropoids, tarsiers share some traits with anthropoids but not lemurs and lorises. Paleontological data supported a linking of adapids and anthropoids. Comparitive anatomy (hemochorial placenta, presence of a retinal fovea, for example) and biochemical data supported a relationship between tarsiers (and consequently omomyids) and anthropoids. This led to something of a stalemate. If tarsiers (and hence omomyidae) were more closely related to the anthropoids (as the anatomical and biochemical data suggested) then adapids (as the paleontological data suggested) couldn't be. Which was right. A very intersting solution to this problem was presented by Gingerich and Schoeninger in 1977. The suggestion wasn't paid much attention to until 1986, when Rasmussen (in his 1986 paper "Anthropoid Origins: A Possible Solution to the Adapidae-Omomyidae Paradox") revived it. Grant the paleontological evidence that relates the omomyidae to tarsiers and adapidae to anthropoids. Lemurs and lorises would then form a sister group to both the omomyidae-tarsier group and the adapidae-anthropoid group. Consequently, tarsiers would be more closely related to anthropoids than to lemurs and lorises - which satifies the anatomical and biochemical evidence and the omomyid-tarsier and adapid-anthropoid groups could still be kept - satisfying the paleontological evidence.

I bring this up because of recent news. Once you get past the dreck about the "missing link" and small mammals (?) the article has some interesting points. If I read this article correctly the find would actually support Rasmussen. From the article:

The fossilised bones, which are thought to be between 37 and 47million years old, were found in Germany’s Messel Shale Pit, a disused quarry near Frankfurt famous for its fossils.

The team who examined the young female animal say it has some resemblance to a lemur, a mammal with a distinctive tail that is found to this day in the forests of Madagascar.

But Sir David’s documentary will explain that the researchers have, controversially, concluded the fossil ‘is not simply a lemur’ but from a related group of primates which evolved into monkeys, apes and human beings.

This supports the idea that lemurs and lorises are the sister group to two clades composed of omomyidae and tarsiers in one and adapids and anthropoids in the other...

Update 1: Brian has an excellent post on the subject

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Saturday, May 09, 2009

Remodeling In Progress

Well, after three years or so I am back at my old blog. Trying to spruce it up a little. More to come...

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