Devonian Trilobite With Eyeshades Found – Erbenochile

Richard Fortey of the Natural History Museum in London bought the only known complete specimen of this fascinating new trilobite from Morocco, the site of many fancy spiked trilobites. A pygidium of another specimen was reported in 1995. This new specimen is dated to 395 MYA, belongs to the Order Phacopida and is named Erbenochile erbeni. Its most outstanding feature is its eyes. Trilobites normally have two kinds of eyes – holochroal made up of many (up to a thousand) minute lenses, and schizochroal with fewer larger biconvex lenses often separated by sclera (includes the Phacopida). This fossil has eyes that are like twin towers with 560 lenses in vertical rows of 18 that are curved strongly from front to back. The field of vision covered the entire surface above the sediment where the trilobite lived and it could even see backwards over its own thorax. The top edges of the eyes fold back over to serve as a sunscreen to the eyes below. Since this would not be needed at night, they believe that it was most active during the day when this shield would have been effective. The report is from the article in Science (Vol. 301, Sept. 19) by Fortney and Chatterton. If this feature made them safer from predators and better able to find food, I wonder why more of them haven’t been found?

Earlier Date for Plant Move to Land

A report in Nature (Vol. 425, Sept 18) by Charles Wellman of the University of Sheffield, UK dates early plants on land about 470 MYA. Previously the earliest land plants were dated to about 425 MYA but spores have been found at the 470 MY dates also. However, it was difficult to find the parent plants to prove that the spores were not from algae. These early plants were like the liverworts of today and were very tiny. The found them in bore holes in rocks deep below the desert in Oman. The spores they found indicate that they were from land plants and not from marine algae. Some of them were different from most land plants today in that they were joined together in groups of two or four which is similar to some liverworts today. To find the parent plants they passed the material through sieves and found some elongated disc shaped objects that turned out to be groups of spores. They are similar to the spore bearing organs of land plants. The spore packet wall is similar to that in liverworts also. There are still skeptics since the actual plants have not been identified yet. But on the other end there are those who believe that plants were on land as early as the Precambrian (700 MYA) – they just haven’t been found yet.

Earliest Sauropod Found in South Africa – Antetonitrus

Parts of a basal sauropod dinosaur were found in the Upper Triassic sediments show adaptations to quadrupedalism that led to the evolution of very large plant eaters in the Jurassic. It is older than Isanosaurus attavipachi from Thailand that consisted of some associated bones that were dated to the Late Triassic. However, these few bones were enough to differentiate it from the more common prosauropods of the time. This new dinosaur is reported in the Proceedings of the Royal Society of London (Vol. 270, 2003) in an article by Adam Yates et al. Antetonitrus ingenipes (named for “before thunder” and “massive foot”). The holotype is a partial skeleton including most of the legs, some vertebrae, ribs, and scapulae. It was a small robust animal estimated at 9 meters (29 feet) long and 2 m (6.5 ft) high at the hip. It was not a mature individual based on the sutures in the vertebrae. The elongated forelimbs, modified femur, and shortened metatarsus are adaptations for quadrupedalism. However, it does maintain a primitive character of a grasping hand.

Large Rodent Found in South America - Phoberomys

Goya is the nickname given to an 8 million year old rodent fossil found in Venezuela. It probably weighed about 1,500 pounds with a long tail and continuously growing teeth for grazing on grass. It is named Phoberomys pattersoni after Brian Patterson of Harvard. The rodents probably grew to such large sizes in South America because of the lack of large predators (except for large crocs up to 33 feet long) that are found on the other large continents. After the land bridge to North America 3 MYA many larger predators occurred and this large rodent disappeared. Its nearest living relative is the pacarana that is a 30 pound animal found in the Amazon jungle.

Study of Lice and First Clothing

Head lice and body lice are different. The head lice live and feed only on the scalp and body lice live only in clothing and feed on skin. A researcher Mark Stoneking at the Max Planck Institute in Leipzig Germany looked for the origins of the two species. By comparing DNA of modern lice from humans and chimps, he has determined that the body lice diverged from head lice about 72,000 YA (give or take 42,000 years). This infers that the origin of clothing use with modern humans is much earlier than the body lice origin. Since clothing is not preserved, it is hard to get a solid fix on its first usage. Sewing needles have been identified as far back as 40,000 YA and pottery and figurines show clothing worn 27,000 YA. Some question whether clothing might have been worn even much earlier based upon the cold climates where Neanderthals lived some 500,000 YA. Stoneking’s DNA study also showed that the lice in Africa were more genetically diverse than found in other parts of the world. This may imply that they arose where modern humans arose in Africa, supporting the Out of Africa Theory over the Multiregional Theory of human evolution. Interesting study.

New Jurassic Tyrannosaurid from Portugal –Aviatyrannosaurus

Oliver Rauhut reports in Paleontology (Vol. 46/5) of finding a fragmentary theropod from the Upper Jurassic of Portugal which he has named Aviatyrannus jurassica (tyrant’s grandmother from the Jurassic). The holotype is an almost complete right illium. Other material found nearby include partial illium and ischium and several premaxillary teeth. The only other early tyrannosaurid known is Stokesosaurus from the Morrison Formation here in North America. In 2000 Rauhut attributed this material to Stokesosaurus, but further study showed structural differences. This strengthens the biogeographic connection between the early tyrannosaurids of the Morrison and Portugal in the Late Jurassic. In the Lower Cretaceous they are known from Europe and Asia and by the Late Cretaceous they are known from Asia and North America. Indications also show that tyrannosaurids started out small and only got really big in the Late Cretaceous.

Karen Nordquist, ESCONI Paleontology Study Group

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