Welcome to my Metazoic site! This site discusses the existence of the creatures to come along after humans will be extinct. I first became interested in a world after man when I acquired my first copy of Dougal Dixon's After Man: A Zoology of the Future in 1992. However, I unwittingly created creatures that did not exist from the time I was about 8 years old. But it was after I obtained a copy of that book (now a collector's item) that I decided to take these same creatures I created as a child and make them more realistic in an evolutionary sense. Though it may be hard for a lot of us to grasp, humans will soon become extinct. One of the biggest factors of how this will happen is the current overpopulation rate. Which is why I don't contribute to the population. I created this world with little more than mammals fulfilling all ecological niches with the help of some friends. I even gave the era of the age after man a name, I called it the Metazoic, derived from the words for "After-era" (Meta, meaning after, and zoic meaning era). We are now in the Cenozoic era. To view all the animals I have created since I began this project, you can go to the "Meet the Mammals" section of this site. To discuss your own ideas about what you think will happen in the future world, and share your ideas with others, please feel free to leave a comment.
One more thing, some of you may find this site quite offensive, and you have a right to your own opinion. But please respect my right to have an opinion too. I'm not saying there is no GOD, I believe it was HIM who got the ball rolling. But I believe after that, evolution took over. There is so much more evidence of evolution than there is of creation. Even that going on right under our noses. Other than that, enjoy yourself and visit our many links.
Friday, May 14, 2010
All Modern Life Derived From One
All Modern Life on Earth Derived from Common Ancestor
A single, primordial event likely yielded the array of organisms living today. Fri May 14, 2010 05:15 PM ET
Content provided by Tina Hesman Saey, Science News
One isn't such a lonely number. All life on Earth shares a single common ancestor, a new statistical analysis confirms.
The idea that life-forms share a common ancestor is "a central pillar of evolutionary theory," says Douglas Theobald, a biochemist at Brandeis University in Waltham, Mass. "But recently there has been some mumbling, especially from microbiologists, that it may not be so cut-and-dried."
Because microorganisms of different species often swap genes, some scientists have proposed that multiple primordial life forms could have tossed their genetic material into life's mix, creating a web, rather than a tree of life.
To determine which hypothesis is more likely correct, Theobald put various evolutionary ancestry models through rigorous statistical tests. The results, published in the May 13 Nature, come down overwhelmingly on the side of a single ancestor.
A universal common ancestor is at least 102,860 times more probable than having multiple ancestors, Theobald calculates.
No one has previously put this aspect of evolution through such a stringent test, says David Penny, a theoretical biologist and Allan Wilson Centre researcher at Massey University in Palmerston North, New Zealand. "In one sense, we are not surprised at the answer, but we are very pleased that the unity of life passed a formal test," he says. He and Mike Steel of the University of Canterbury in Christchurch, New Zealand, wrote a commentary on the study that appears in the same issue of Nature.
For his analysis, Theobald selected 23 proteins that are found across the taxonomic spectrum but have structures that differ from one species to another. He looked at those proteins in 12 species -- four each from the bacterial, archaeal and eukaryotic domains of life.
Then he performed computer simulations to evaluate how likely various evolutionary scenarios were to produce the observed array of proteins.
Theobald found that scenarios featuring a universal common ancestor won hands down against even the best-performing multi-ancestor models. "The universal common ancestor (models) didn't just explain the data better, they were also the simplest, so they won on both counts," Theobald says.
A model that had a single common ancestor and allowed for some gene swapping among species was even better than a simple tree of life. Such a scenario is 103,489 times more probable than the best multi-ancestor model, Theobald found. That's a 1 with 3,489 zeros after it.
Theobald's study does not address how many times life may have arisen on Earth. Life could have originated many times, but the study suggests that only one of those primordial events yielded the array of organisms living today. "It doesn't tell you where the deep ancestor was," Penny says. "But what it does say is that there was one common ancestor among all those little beasties."