Green Polar Bears: A Consequence of Specialization

[Nordue]

Green Polar Bears
A Consequence of Specialization
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A case study presented by Tonbei

• No, there hasn't been a new subspecies discovery. And this isn't the result of a recent genetic mutation. These bears weren't born this way. And this isn't a zoo's idea of getting ready for the Holiday season either . What is happening is simply a consequence of the polar bear's adaptations to a specific set of environmental conditions.
  
  As most people know, polar bears are adapted to an arctic environment. Their species has evolved various traits that make them well-suited life in very cold climates. So what can happen when specialized animals like the polar bear are placed in different climates around the world, through zoos? Green polar bears!
  
  In areas with warmer climates, higher temperatures can cause algae to grow rapidly in water bodies such as polar bear swimming pools, despite regular cleanings. Polar bears have hollow over coat hairs that the algae can become trapped in and make the bears appear green with the trapped algae.
  
  So now you’re probably wondering: why aren’t other zoo animals turning green too? This is where the specific adaptations of the polar bear to cold climates come in. Polar bears have hollow guard hairs to help trap the precious heat that constantly escapes from their bodies. The transparent-colored hairs also reflect incoming visible light but allow infrared light to pass though to their skin and warm it. That's why polar bears are turning green, while other animals are not.
  
  Question:
  The polar bear is a model animal for climate change, especially in the arctic. Can you think of reasons why that might be, in light of species specializations to certain environmental conditions?
  
  Thanks for reading,
  • Tonbei
  Sources of information:
  http://www.msnbc.msn.com/id/26591321/ns ... LKlfofAc_g
  http://www.nature.com/nature/journal/v2 ... 445a0.html
  (My biodiversity course notes. Sorry, no link!)

[BlackWarrior]

Wow! This is definitely an interesting read! First off, thanks for sharing and writing all that up, Tonbei! Very cool! I went ahead and looked up some images of these bears and they are actually green!? Or appear green.. ^^ I find it particularity interesting that they would adapt to that extent. Many winter animals (it seems in general) have further adaptations that we have physically seen as observers. Such as the snow hare adjusting the color of its coat depending on the season. Many of the birds in those areas have similar feather techniques. Sure, other animals adapt in different ways, but we often don't notice drastic changes in their appearance; like these polar bears.. ^^: Neat study!

[Nordue]

• Hey BlackWarrior! Your sure welcome. Thanks for taking the time to read and comment .
  
  You mention some good examples there of other arctic specializations. I'll add another: wolves are regional heterotherms. This means that they are able to keep the temperature of certain parts of their bodies below 37 degrees Celsius through countercurrent exchanges (exchange of heat) between their closely placed veins and arteries. Literally, the temperature of their foot pads can be maintained at 0 degrees Celsius!
  
  If anyone needs more information, check out the 33nd slide of this file I found online: http://classes.uleth.ca/200801/biol4850 ... lation.pdf. Don't worry about the letters, just look at the temperatures in the various parts of the wolf leg.

[BlackWarrior]

Not a problem! ^^
I dont think I've actually ever heard of that before about wolves, but again, that's very interesting. I do know our bodies automatically send more blood towards the cold parts of our bodies in order to keep them heated, but this:

• Hey BlackWarrior! Your sure welcome. Thanks for taking the time to read and comment :) .
  
  You mention some good examples there of other arctic specializations. I'll add another: wolves are regional heterotherms. This means that they are able to keep the temperature of certain parts of their bodies below 37 degrees Celsius through countercurrent exchanges (exchange of heat) between their closely placed veins and arteries. Literally, the temperature of their foot pads can be maintained at 0 degrees Celsius!
  
  If anyone needs more information, check out the 33nd slide of this file I found online: http://classes.uleth.ca/200801/biol4850 ... lation.pdf. Don't worry about the letters, just look at the temperatures in the various parts of the wolf leg.

New information for me.. I will definitely look into reading the link you provided above, seeing as it would probably be a very intriguing topic of discussion. So if animals are able to adapt in some unexpected ways, why can't polar bears turn green without questioning!? ;)

[Nordue]

• Wait...not sure if sarcasm or actual question BlackWarrior !

[BlackWarrior]

• Wait...not sure if sarcasm or actual question BlackWarrior !

Sarcasm -- Haha Meaning ~ If all these animals can have such crazy adaptations, polar bears turning green should seem pretty normal.. Sort of? Then again, how can animals turning green be natural at all? :b

[Nordue]

• Well, it is completely natural because of evolutionary adaptation over successive generations magic! Pure, sparkling, unspoiled magic! Don't tell anyone .