A special list to celebrate the New Year… A little tradition on this blog is to collect my favorite hominin #FossilFriday tweets of the year, from number 10 to 1. This is the sixth list!
What is a ‘FossilFriday’? Every Friday, people post pics of their favorite fossils using the hashtag #FossilFriday, mainly on Twitter. This can be about famous specimens, odd fossils, museum collections, rare photos, scientific papers or blog posts. I love to join & tweet about hominin fossils. One more time, let’s start!
10. Out of the box: ER 1805, Homo habilis. By Dr Andy I. R. Herries @Ozarchaeomaglab
Another year-end list! This one is becoming an old tradition on this blog… My favorite hominin #FossilFriday tweets of 2018, from number 10 to 1.
What’s a ‘FossilFriday’? Every Friday, people post pics of their favorite fossils using the hashtag #FossilFriday, mainly on Twitter. This can be about famous specimens, odd fossils, museum collections, rare photos, scientific papers or blog posts. I love to join it & tweet about hominin fossils. Now, let’s go!
10. Unusual picture of a very iconic fossil, ER 1813 Homo habilis:
9. New studies on old fossils. Did Cro-Magnon 1 have neurofibromatosis type 1?
8. This gorgeous hand of Australopithecus sediba:
This is the 4th one of a little tradition, my special Paleoanthropology annual report… The list of my favorite hominin #FossilFriday tweets in 2017, from number 10 to 1.
What’s a ‘FossilFriday’? Every Friday on Twitter, people share pics of their favorite fossils, related scientific papers or blog posts, by using the hashtag #FossilFriday. This is a great manner to show famous or rare pieces of museum collections, and to share research works. Every Friday I love to join & tweet about a different hominin fossil. Now, let’s go!
10. Very nice National Geographic hologram cover from November 1985, starring the Taung child:
The supraorbital torus (or brow ridge) is a very distinctive morphological trait in most of our hominin ancestors. What purpose does this feature serve? A few hypotheses around this topic are:
- Dissipation of heavy chewing forces, produced by the jaw muscles and transmitted around the nose and the eye sockets.
- Evolutionary result of the fulfilment of spatial demands between the orbits and the brain case.
- Capacity to dynamically express affiliative prosocial emotions through highly mobile eyebrows.
- Reinforcement of the frontal bone which was weaker in all the hominin species before Homo sapiens. This is a similar idea to explain the development of the chin in modern humans, as a reinforcement of a weaker jaw.
- Protection of the skull and the eyes against blows.
- A signaling effect, accentuating aggressive stares, thus its large size could have been sexually selected through generations. Is the lack of brow ridges related to self-domestication in modern humans?
However, many huge supraorbital tori are hollowed inside with large sinuses (for example: Petralona), suggesting that they did not bear or transmit physical forces from blows to the head or heavy chewing. Another iconic skull, Kabwe 1, has a much larger browridge than the minimum required to fulfil spatial demands, and its size has little impact on mechanical performance during biting.
I like the idea to think about a combination of several factors which made evolution work for a few million years. This post describes the supraorbital tori of 22 iconic hominins:
Al 444-2: The largest Australopithecus afarensis skull yet discovered has an expansive supraorbital torus, thickened laterally and continuous superiorly-posteriorly with no interruption.
Sts 5 (Mrs. Ples) has a relatively small supraorbital torus, double arched in the front and projecting glabella. Another Au. africanus skull with many similarities is Sts 71, with a less broad torus in comparison to Sts 5, but with a similar expanded glabella.
Supraorbital torus: Sts 5 (centre)-credit Wikipedia, AL 444-2 (left) and Sts 71 (right)-credit Roberto Sáez