Afarensis is a 3.5-2.8 million year old hominin from the Kada Hadar member of the Hadar formation in the Middle Awash, Ethiopia. He is approximately 41 inches tall, weighs approximately 60 pounds and has a cranial capacity of a whopping 410 cc (approximately). Afarensis is currently considered to be transitional between apes and humans and displays some traits of both. Since he spends a lot of time on the couch watching monster movies, some observers question whether he is an obligate biped (although no one has observed him climbing a tree). He also has a blog called 
PZ has the story on the Mesozoic Beaver along with pictures of the fossil. For those who don't have access to Science National Geographic has a story as well.
Speaking of National Geographic, they also have an intersting article on the recent AAAS session concerning the preservation of dinosaur soft tissue. Mary Schweitzer ( the scientist who discovered the T-Rex blood vessels) gave a presentation. One of the surprising statments in the article:
Mary Schweitzer, the North Carolina State University paleontologist who announced the finding, said her team has now repeated that feat with more than a dozen other dinosaur specimens.
It's suprising because I, for one, had not heard about the other specimens. The article also gives an interesting glimpse into the methods used to find the specimens:
Until now, Schweitzer said, "the standard wisdom was that if you dissolve away the mineral [in fossils], there would be nothing left." That has been the case in about half of the specimens she has examined.But the other half have yielded remarkably consistent results.
She also has a possible explanation for the preservation of the soft tissue:
Schweitzer said a central focus of her research is to explain this phenomenon, which was once thought to be impossible.
New findings—not yet published—have led her to suggest one possible explanation. The key, she believes, may be the iron content of the blood and muscle proteins hemoglobin and myoglobin.After an organism dies, iron released from these proteins as they degrade may trigger the formation of highly reactive forms of oxygen known as free radicals. Other heavy metals in the environment may produce the same effect.
Schweitzer thinks these metal-generated free radicals may trigger the formation of longer molecular chains, known as polymers, which essentially bind and lock remaining cellular structures in place.
"Eventually, the polymerized remains become inert, free from attack from the outside and further chemical change," Schweitzer said.
Which brings us to:
Lampreys!
According to Science Daily a team of researches has discovered that the protein responsible for building cartilage is none other than collagen...Which has some interesting implications:
"It was thought collagen was a relatively recent invention in vertebrate evolution that unites us with reptiles, amphibians, sharks and bony fishes, while the lamprey skeleton was based on quite different proteins," said Martin Cohn, Ph.D., a developmental biologist and associate professor with the UF departments of zoology and anatomy and cell biology. "Knowing that lampreys also use collagen to build their skeletons makes sense. Lampreys and jawed vertebrates inherited the same genetic program for skeletal development from our common ancestor."[you can go here for more info on bone formation and collagen]
Basically, the team used gene sequencing and gene cloning to isolate the genes responsible - in this case for type II collagen. Additionally, they isolated a gene called Sox9 which also regulates collagen gene activity in vertebrates:
The results indicate the collagen-based skeleton evolved before the jawed and jawless vertebrates split into different paths, not afterward. In addition, the research shows that scientists have to dig beyond bone and cartilage to unravel vertebrate relationships, according to Michael Caldwell, Ph.D., an associate professor of earth and atmospheric sciences and of biological sciences at the University of Alberta.
As the researchers put it:
"It is the lack of bone in these animals and the supposed uniqueness of their cartilage, that has for so long plagued scientists in their attempts to place them in the evolutionary scheme. An entire taxonomy was created for animals that basically have a head at one end and cartilage to hold it together, but no bone. But this work says the common feature of vertebrates is not the presence or absence of bone, but the presence of a shared gene system that produces cartilage. This conclusion is illuminating and extremely important."
Fascinating...
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