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Phylogenetic tree of the lemurs based on mobile genetic elements taken from a paper I just published in PLoS ONE. Link to the article by clicking on the photo.
(Ed.: fascinating! Thank you!)
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Skull of juvenile Bornean orangutan (top) compared to adult Homo sapiens
Like most great apes, Bornean orangutans (Pongo pygmaeus) have large, sharp, canine teeth. However, these do not grow in until the juvenile orangutan loses its milk teeth, a couple years after weaning (typically between 4-6 years of age).
You can see the evolutionary differences in diet between orangutans and humans, simply by looking at the teeth and shape of the skull. The orangutan has large, broad molars, sharp incisors, and mandibular musculature that has a very broad attachment point on the skull. Bornean orangutans are generally vegetarian, feeding on leaves, berries, and even bark at times. The broad molars are necessary for grinding and breaking down roughage in their diet.
While the human skull given is not the best example, we have smaller molars, weaker mandibular muscles, and fairly dull incisors and canines. Homo sapiens evolved as strict omnivores, but with a very distinct difference from our more simian (and even most of our hominid) ancestors - we cooked our food. Though the roughage early humanity consumed was much tougher than what we eat today (unless you eat roots and nutmeats as a primary diet), cooking foods such as meats and roots broke them down before we ate them. Our skulls required less space for jaws and jaw muscles, and we required less energy to eat than ever before.
Die Säugthiere in Abbildungen nach der Natur. J.C.D. Schreber, 1774.
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Brontosaurus
Mounted skeleton was on display at the American Museum of Natural History
Reconstruction by Charles Knight
When: Holocene (1879 to 1903)
Where: Scientific literature and museums on the east coast of the USA. Found even today in public consciousness and outdated dinosaur books.
What: Brontosaurus is perhaps the most well known of the sauropod dinosaurs. Too bad it never really existed! The history of this name and why it became so popularized starts in 1877 when the paleontologist Othniel Charles Marsh applied the name Apatosaurus to a sauropod specimen. This specimen was not very complete and mostly represented by vertebrae and a pelvis. Two years later he erected the name Brontosaurus based on an almost complete skeleton that was missing its head. Headless sauropod skeletons are fairly common, but in this case this missing head only served to make the story even more complicated.
This missing head was obviously a problem when the Peabody Museum of Natural History at Yale wanted to mount its specimen of Brontosaurus for display. There was great debate over which head to use, which some camps wanting to use one that resembled Diplodocus but others rallied behind a Brachiosaurus type skull. This latter skull was what Marsh had envisioned in his publications on Brontosaurus, so after much heated debate a Brachiosaurus type skull was attached to the previously headless skeleton. This skeleton was unveiled to the public in 1905 to great fanfare and soon after the American Museum of Natural History in New York City had its own Brontosaurus on display, with an identical head to the Yale specimen.
So the general public had a firm concept of the dinosaur Brontosaurus! It was an easy to remember and pronounce name, this is what it looked like, and hey look we even have all of these lovely reconstruction showing these great lumbering beasts in prehistoric swamps. Too bad everything was wrong. And even worse, it was KNOWN to be wrong by some workers who were shouted down by others. In 1903, two years before the specimen was mounted at Yale, a paper was published Elmer Riggs at the Field Museum of Chicago that declared that the bones known for Apatosaurus that overlapped with those of Brontosaurus showed that these two animals were the same. He concluded that Brontosaurus was not a valid name as it was two years younger than Apatosaurus. Even worse, remember the great head debate? Totally wrong. Later fossil finds have confirmed that a Diplodocus style head should have been used. These skulls are much more elongated and flatter than the high domed skull that was used for the Brontosaurus mount.
So not only is the name not valid, but the anatomy of the animal isn’t even anything that ever existed in nature! It is a chimera of different species. Also sauropods were not aquatic swamp dwellers, they were 100% terrestrial creatures.
Poor Brontosaurus.
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Clitoria ternatea - Butterfly pea, Aparajita, Pigeon-wings, Blue pea vine
Flora de Filipinas Atlas II. Francisco Manuel Blanco, 1880-1883.
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Duck-billed Platypus
From Shaw’s 1807 lecture at the Royal Institution:
“If we rank this animal according to the Linnaean arrangement of quadrupeds, it must of necessity belong to the order Bruta, being destitute of teeth; but if we rank it according to its general habit or appearance, it might find a place among the Seals and other web-footed quadrupeds. The fact however is, that it may be questioned whether it really and properly belongs to the tribe of Mammalia or not; since no examination hitherto made, of such specimens as have been brought over, preserved in spirits, have exhibited the least appearance of teats for suckling the young…”
Platypuses are curious creatures when it comes to lactation - we now know that they do indeed lactate and provide milk for their young, but not from “teats”. The mammary glands under the skin along a short line on the female’s stomach secrete milk when stimulated, and this milk gathers on a tough, fibrous hair. The puggles can then consume it in a manner that looks much like a duck drinking water or eating crumbs in a lake. It’s a very odd sight.
Zoological Lectures Delivered at the Royal Institution in the Years 1806 and 1807 by George Shaw. Pub. 1809.
