July 12, 2019

Archaeopteryx

In 1861, a newly discovered fossil feather was about to change the way we view life. This fossil feather, discovered by Hermann von Meyer, belonged to a long extinct species called Archaeopteryx lithographica. This was the first trace of a bird-like animal to have lived during Pre-Tertiary times.

This discovery supported Darwin’s theory of evolution, which had been developed around the same time. It represented a transitional species between dinosaur and bird, providing a link between Reptilia and Aves.

Archaeopteryx possessed a reptilian tail and clawed fingers on the tips of its wings. However, it also had a very slim, bird like neck and, more crucially, well developed feathers. Although feathers had previously been evolved in dinosaurs for various purposes (such as thermal insulation), those found on Archaeopteryx formed primitive wing-like structures. In addition to these ‘wing feathers’, Archaeopteryx also possessed tail feathers, which may have served to work with the wings to increase lift. Despite all these aerodynamic adaptations, the lack of hollow bones would have greatly reduced the time of flight in these primitive birds.

Although their function may have been reduced in the earliest birds, two mechanisms driving the evolution of wings have been hypothesised:
1) Arboreal ancestors evolved wings so that they could glide to the ground.
2) Terrestrial ancestors evolved wings so that they could jump up and fly to higher places.

Many more theories have also been put forward regarding the Archaeopteryx and the evolution of birds, including some which regard an even older species as being the missing link between dinosaur and bird (and thus confirming the bird-like nature of Archaeopteryx). Only through the discovery and analysis of previously hidden fossils can we gain a greater understanding of evolution, not just of Archaeopteryx, but of life itself.

-Draslik

Sources:
-https://www.earthmagazine.org/article/benchmarks-september-30-1861-archaeopteryx-discovered-and-described. Visited on 12/07/19.
-Moody, R. T. J., Buffetaut, E., Naish, D. & Martill, D. M. (eds) Dinosaurs and Other Extinct Saurians: A Historical Perspective. Geological Society, London, Special Publications, 343, 251–263. DOI: 10.1144/SP343.15.
-C. Pellant, H. Pellant, 2007, Fossils a Photographic Field Guide, New Holland Publishers, London. ISBN 978 1 84537 336 8.
-https://ucmp.berkeley.edu/diapsids/birds/archaeopteryx.html. Visited on 12/07/19.
-Foth, C., Tischlinger, H. & Rauhut, O. W. M. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature 511, 79–82 (2014). doi:10.1038/nature13467.

Posted on July 12, 2019 17:49 by draslik draslik | 1 observations | 0 comments | Leave a comment

Archives