Piltdown Man

For the Book Review assignment I have been reading "Piltdown Man and Other Hoaxes" by Jonathan Maxwell.  The main hoax discussed is Piltdown man, which was once thought to be a missing link in the evolutionary lineage of humans.

A skull was found in the English county if Sussex in 1908.  It appeared to be closely related to a human's, but the jaw appeared to be very ape-like, and its discoverer, Charle Dawson, hurried home with his find and began some research.  Over the years, Dawson gained many followers who strongly believed Piltdown man was a missing ancestor of humans.  But of course with followers comes those who deny it.  The people against Dawson ranged from the religious community to his fellow scientists who believed this discovery was too good to be true.

Many of his followers were world renowned scientists, so the oppositions against  Piltdown man began to slim, except for the Americans.  American scientists refused to believe that there was the possibility of human ancestors in Europe, but none in America.  At the time, no one knew where humans actually originated (which was in Africa), so there was much dispute among different countries because they all wanted the origin of humans to be from their homeland.  Americans believed humans originated in America, so therefore Piltdown man had to have been a hoax.

Years later, in 1953, long after Charles Dawson passed away, Piltdown man was indeed discovered to be a fraud.  It turns out, the skull of the creature was a human skull and the jaw of an orangutan that were both artificially aged.  They were dropped near each other into a gravel pit left to be discovered.

To this day, the mastermind behind this hoax remains unknown, but many believe it was the discoverer of Piltdown man, Charles Dawson, that forged this "scientific breakthrough".

Hind Feathers and Flight of Early Birds

It is an extremely unknown fact that many dinosaurs and other reptiles possessed feathers to regulate their body temperature because they were all cold-blooded.  However, recent discoveries show that early birds had large legs similar to an ostrich, but their legs did not have tiny feathers, rather they were covered in long feathers that appeared to have been used for flight.  “A bizzare hind wing formed by a large pennaceous feathers (feathers with stiff vanes) along with the metasaurs is known in several non-avian dinosaurs and may have played an important role in the evolution of flight on the line to birds" (Zheng). 

 

Fossils of early birds with strange feathered hindlimbs were discovered and point to the fact that early birds may have had a similar body structure to a biplane, an airplane with two sets of wings, and upper and a lower.  Then, as evolution proceeded, the hindlimbs of birds shrank and lost their feathers.  And their forelimbs grew larder and grew longer and more efficient feathers.  Now the only feathers on the hindlimbs of modern birds are tiny and fluffy and used only for insulation purposes.  

The use of hindlimbs during flight was most likely much easier to accomplish than flying like today's birds.  Without the use of their hindlimbs, it it likely that birds never would have been able to leave the ground.  

            

http://www.sciencemag.org.proxy.libraries.rutgers.edu/content/339/6125/1309.full

Origin of Venom

             Venom is a widely used trait among the animal kingdom.  It has gone through convergent evolution throughout the animal kingdom.  Convergent evolution is when the same trait evolves for the same reasons, but in completely different lineages.
             Many animals use venom either to hunt or to protect themselves from predators.  "Venom is the mark of a special club, a select subset of the animal kingdom. It includes vipers, jellyfish, spiders, scorpions, centipedes, bees, cone snails, newts, platypus, and even a primate" (Zimmer).  Venom is made up of molecules specifically designed to harm another animal.  There are two types of venom, neurotoxins and  hemotoxins.  A neurotoxin is designed to break down the nervous system and the brain, causing a swift death in many animals.  A hemotoxin is designed to break down blood cells and organs, causing a slow and painful death.

 

            All the animals containing venom evolved this unique trait completely separate, but only for two main reasons.  They all evolved venom to either hunt prey or defend from predators.  Snakes, scorpions, and spiders developed venom to both hunt and defend themselves.  The black widow spider has one of the most potent venoms in the animal kingdom, but it cannot inject larger animals (such as humans) with enough venom to cause immediate fatality.  Many other animals like poison dart frogs, puffer-fish, and even some mammals developed venom to protect themselves from predators.  The poison dart frog has a unique, bright colored pattern to warn predators that its skin is highly toxic.

            Venom is a highly unique trait, but it is extremely advantageous to many different animals all throughout the animal kingdom. 

http://phenomena.nationalgeographic.com/2013/01/09/on-the-origin-of-venom/