  Collagen is the main protein of connective tissue in animals and the most abundant protein in mammals,[1] making up about 25% to 35% of the whole-body protein content.I â¦ t is naturally found exclusively in metazoa, including sponges. [2] In muscle tissue it serves as a major component of endomysium. Collagen is the main protein of connective tissue in animals and the most abundant protein in mammals,[1] making up about 25% to 35% of the whole-body protein content.
The Southern Cassowary - The Most Dangerous Bird on Earth. Sunday, 1 September 2013. Ask a ten year old what the largest bird in the world is and the chances are you will get the right answer â the ostrich. Asked about the second largest and the odds are still very good that they will be able to name the Emu.
Due to Endangered Species Act protection, these majestic red-crowned birds made an amazing comeback from the brink of extinction when only 15 birds survived in 1940. Following decades of effort, whooping cranes are now on the path to recovery, but this success could be erased by the proposed Keystone XL Pipeline.