Tuesday, 15 November 2016

Monday, 14 November 2016

AMMONITES OF THE ARNIOCERAS BEDS

Ammonites (and two gastropods) from the Arnioceras beds near Last Creek in the Canadian Rocky Mountains. The fossils found here are from the Lower Jurassic, Lower Sinemurian, Little Paradise Member of the Last Creek formation. This site is part of the research area for Dr. Howard Tipper, GSC (who is hugely missed) and Dr. Louise Longridge, University of British Columbia.

Several ammonites species can be found here including Arnioceras semicostatum & Arnioceras miserable. The two gastropods you see in the central block have yet to be identified to species. Here's hoping a nice grad student takes an interest. The rare but lovely gastros from this area would make an excellent thesis. Perhaps comparing their distribution to their counterparts in Europe.

Wednesday, 9 November 2016

MEGATHERIUM AMERICANUM





In 1788, this magnificent specimen of a Megatherium sloth was sent to the Royal Cabinet of Natural History from the Viceroyalty of Rio de la Plata.

The megaterios were large terrestrial sloths belonging to the group, Xenarthra. These herbivores inhabited large ares of land on the American continent. Their powerful skeleton enabled them to stand on their hind legs to reach leaves high in the trees, a huge advantage given the calories needed to be consumed each day to maintain their large size.

In 1788, Bru assembled the skeleton as you see it here. It is exhibited at the Museo Nacional De Ciencias Naturales in Madrid, Spain, in it's original configuration for historic value.

If you look closely, you'll see it is not anatomically correct.

But all good paleontology is teamwork. Based upon the drawings of Juan Bautista Bru, George Cuvier used this specimen to describe the species for the very first time.