Little Foot is among the oldest known hominins in southern Africa. This almost complete skeleton, belonging to the genus Australopithecus, dates back more than 3 million years. We know that it consisted of several species, a few of them possibly living at the same time and that these species consumed a high diversity of food. But regrettably, since the fossils are frequently fragmented, we still do not know precisely what Australopithecus brain of Australopithecus, how they walked or why they evolved in certain ways. Now a combination of Little Foots relatively intact skull and a high technology scanning method called microtomography has helped us uncover some of the answers.
Investigate Little Foots skull.
My co-workers and I used microtomography to virtually investigate Little Foots skull. This method depends on the use of a scanning device that allows us to access very fine details a few micrometers at a time. We explored various anatomical structures of the skull and, more especially, the brain imprints and the interior ear. We then compared what we found to other Australopithecus specimens, and also to fossil remains belonging to different groups: Paranthropus and early Homo. These are geologically younger, which allowed us to track evolution. The brain and the interior ear are also intriguing interfaces between fossil hominids and their physical and social environment.
Studying brain imprints
Through these studies, we may present and explore new scenarios on how our ancestors lived and evolved. Studying brain imprints – The brain can’t fossilize. That implies that any understanding of hominin brain evolution depends on analyzing the imprints of the brain which are preserved on the inside of our skulls, also known as the endocast. The endocast can deliver info regarding the size, shape, and organization of the brain, and also the blood vessel system that feeds it. Regardless of the presence of some cracks and the fact that some portions of the skull are deformed, the Little Foots endocast is relatively complete and preserves clear imprints of the brain.
Little Foots frontal lobes
The imprints of the brain in Little Foots frontal lobes are comparable to the geologically younger specimens of Australopithecus: they show an ape-like pattern that differs substantially from living humans. The visual cortex in the back region of Little Foots endocast, meanwhile, appears to be more expanded than in younger Australopithecus and in living humans, where it’s more reduced. This info is critical since the reduction of the visual cortex in the hominin brain is directly related to the expansion of the parietal associative cortex, which is involved with critical functions like memory, self-consciousness, orientation, attention or tool use. This could mean that those functions weren’t as developed in Little Foot as compared with later hominins. Our hypothesis is that environmental changes about 2.8 million years ago can have led to selective pressure on Australopithecus brain. An unforeseen environment could have changed the habitats and food resources of Australopithecus, and they’d to adapt to survive.