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.

Tuesday, January 24, 2012

Iridescence in Golden Moles

I added irridescence in some mammals in my Metazoic project. Mostly pteropods. I was told that was not possible in mammals. Though polar bears are probably the closest, or were for a long time. Their fur reflects the colors of their surroundings, which is not the same as irridescence, but the structure of each strand of hair would be about the same. Anyway this feature, according to this article, is possible in mammals, and it does exist.

http://news.discovery.com/animals/golden-moles-iridescent-122401.html#mkcpgn=rssnws1

World's First Iridescent Mammal Discovered

By Jennifer Viegas
Tue Jan 24, 2012 07:00 PM ET

Iridescence -- a lustrous rainbow-like play of color caused by differential refraction of light waves -- has just been detected in the fur of golden moles.

Aside from the “eye shine” of nocturnal mammals, seen when a headlight or flashlight strikes their eyes, the discovery marks the first known instance of iridescence in a mammal. The findings, published in the latest Royal Society Biology Letters, reveal yet another surprise: the golden moles are completely blind, so they cannot even see their gorgeous fur.

“It is densely packed and silky, and has an almost metallic, shiny appearance with subtle hints of colors ranging between species from blue to green,” co-author Matthew Shawkey told Discovery News.

Shawkey, an associate professor in the Integrated Bioscience Program at the University of Akron, was first inspired to study golden moles after an undergraduate student of his, Holly Snyder, wrote her honors thesis about iridescence. Snyder is lead author of the paper.

For the study, the scientists pulled hairs from specimens of four golden mole species. Using high tech equipment, such as scanning electron microscopy and transmission electron microscopy, the researchers analyzed the structure of the hairs, down to their smallest elements.

The researchers determined that the hairs are indeed luminescent. They further discovered that each hair has a flattened shape with reduced cuticular scales that provide a broad and smooth surface for light reflection. The scales form multiple layers of light and dark materials of consistent thickness, very similar to those seen in iridescent beetles.

Optical modeling suggests that the multiple layers act as reflectors that produce color through interference with light. The sensitivity of this mechanism to slight changes in layer thickness and number explains color variability.

What remains a mystery is why blind animals would have such eye-catching fur.

Ancestors of the moles were sighted, so it’s possible that the iridescence is a carryover from those times. “However, the moles have diverged considerably from these ancestors so there had to be some selection pressure other than communication to keep their color intact,” Shawkey said.

Another possibility is that the fur somehow wards off the mole’s sighted predators. But Shawkey said shiny fur “would seem to make them more conspicuous,” doing just the opposite. The moles are not poisonous, so the coloration does not serve as a warning to other animals.

The researchers instead think that iridescence may be a byproduct of the fur’s composition, since the structure also streamlines the mole’s profile and creates less turbulence underground, permitting the animals to move more easily through dirt and sand.

“Many of the nanostructures producing iridescent colors have non-optical properties like enhanced rigidity (think mother of pearl) or enhanced water repellency (such as seen in Morpho butterflies),” Shawkey explained. “In the former case, the color, like in the moles, clearly has no communication function and is a byproduct.”

Iridescence has been around for at least 50 million years, since beetles from that time with the unique coloration have been unearthed. An ancient, iridescent bird feather dating to 40 million years ago has also been documented, as have early shells. Now peacocks, hummingbirds, sunbeam snakes, birds of paradise, the rainbow skink, and many fish flash their iridescence.

Daniel Osorio, a professor of neuroscience at the University of Sussex, has studied iridescence in birds. Surprisingly, one of the most beautiful examples may belong to the common feral pigeon. The pigeon’s neck feathers shift from green to magenta, but often look drab gray to human eyes.

Osorio told Discovery News, “In fact, this gray may be a remarkable and very unusual color to birds that can probably see more colors than us.”

In the future, Shawkey and his team hope to study the phenomenon more, to better understand the function of iridescence in the moles and other species.

4 comments:

El Squibbonator said...

Do you have any descendants of golden moles in the Metazoic?

TimGal said...

So far I haven't. I can imagine not much about them would change though. JMO.

El Squibbonator said...

I dunno, I was thinking they might make a good ancestor for a group of mammalian "snakes": specialized burrowers or sand-swimmers with limbs that have almost entirely atrophied and prey on things like rodents, lizards, and large insects.

TimGal said...

That could be interesting.