Darwinius

Darwinius is a genus within the infraorder Adapiformes, a group of basal strepsirrhine primates from the middle Eocene epoch. Its only known species, Darwinius masillae, lived approximately 47 million years ago (Lutetian stage) based on dating of the fossil site. The only known fossil, called Ida, was discovered in 1983 at the Messel pit, a disused quarry near the village of Messel, about 35 km (22 mi) southeast of Frankfurt, Germany. The fossil, divided into a slab and partial counterslab after the amateur excavation and sold separately, was not reassembled until 2007. The fossil is of a juvenile female, approximately 58 cm (23 in) overall length, with the head and body length excluding the tail being about 24 cm (9.4 in). It is estimated that Ida died at about 80–85% of her projected adult body and limb length. The genus Darwinius was named in commemoration of the bicentenary of the birth of Charles Darwin, and the species name masillae honors Messel where the specimen was found. The creature appeared superficially similar to a modern lemur. The authors of the paper describing Darwinius classified it as a member of the primate family Notharctidae, subfamily Cercamoniinae, suggesting that it has the status of a significant transitional form (a 'link') between the prosimian and simian ('anthropoid') primate lineages. Others have disagreed with this placement. Concerns have been raised about the claims made about the fossil's relative importance and the publicising of the fossil before adequate information was available for scrutiny by the academic community. Some of Norway's leading biologists, among them Nils Christian Stenseth, have called the fossil an 'exaggerated hoax' and stated that its presentation and popular dissemination 'fundamentally violate scientific principles and ethics.' Franzen et al. (2009) place the genus Darwinius in the subfamily Cercamoniinae of the family Notharctidae within the extinct infraorder Adapiformes of early primates. Darwinius masillae is the third primate species to be discovered at the Messel locality that belongs to the cercamoniine adapiforms, inaddition to Europolemur koenigswaldi and Europolemur kelleri. Darwinius masillae is similar but not directly related to Godinotia neglecta from Geiseltal. The adapiforms are early primates which are known only from the fossil record, and it is unclear whether they form a monophyletic or a paraphyletic grouping. They are usually grouped under Strepsirrhini—including lemurs, aye-ayes and lorisoids—and as such would not be ancestral to Haplorrhini, which includes tarsiers and simians. Simians are usually called 'anthropoid': while this term can be confusing, the paper uses it, as does associated publicity material. Simians (anthropoids) include monkeys and apes, which in turn includes humans.