Five things you didn’t know about… The Animal Kingdom

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The Animal Kingdom is a weird and wonderful place; but there are probably a lot of things you either didn’t know, or at least some misconceptions. Here I’m going to highlight a few of those I found most interesting:

 

  1. Why on Earth do Giraffes have long necks? You would probably think, “Well, to eat food higher up on trees of course, thus making them more likely to survive, thus passing on their genes for a long neck.” This is a sound notion, but in actuality, this seems to only be a bonus of having a long neck; not the primary reason. Most giraffes tend to eat from around 2-4 meters off of the ground, bending down in spite having as much as a 6 meter reach.

    Giraffes "necking".

    The much more likely, and a widely accepted reason, is that giraffes have long necks to please the lady giraffes! “Necking”, by which giraffes fight using their necks, is a ritual where two males fight for dominance, to arouse the interest of a mate. The longer the neck of a male, the more likely he is to win, asserting his dominance, and getting to mate; propagating the genes for a lengthier neck.

     

  2. Next up is chameleons and their skin colour. Chameleons, in fact, have transparent skin, and lower level cells called “chromatophores”, and an even deeper level of “guanine” containing cells. Technically, chameleons are only capable of generating red and yellow pigments; however the guanine containing cells are capable of reflecting blue light, allowing chameleons to gain further colour ranges of blues, greens, turquoises and purples (as well as levels of reds, yellows, oranges and browns purely from pigments).

    A camouflaged chameleon.

    But, for what reasons do chameleons need to change colour? Most people would say camouflage, i.e. blending in with ones surroundings; this is a nice thought, and in actuality there is some truth in it, certain types of chameleon do use camouflage, such as the “Smith’s Dwarf Chameleon”. But the primary use of colour change in chameleons is largely social. They largely alter their colour based on moods, or as a way of communicating to others; lighter colours often imply a desire to mate, where as darker colours tend to show hostility.

     

  3. The fact that all living things die needs little explanation, but did you know there is a species of jellyfish called “Turritopsis nutricula” or “Immortal Jellyfish”. These jellyfish, although of course can die of predation or disease, can theoretically live forever; never dying of old age. The jellyfish species has the following lifecycle; fertilized eggs develop into “planula larvae” on the sea floor, these develop into polyps (small tentacle like colonies) which bud medusa (medusae are the umbrella like and best known stage of the jellyfish). 

    After a few weeks, these jellyfish become sexually mature, and produce offspring.  The jellyfish will then put its cells through a process called “transdifferentiation” in which it converts its differentiates cells into a new form; it will reabsorb its tentacles before becoming a polyp colony (again) and continuing the life cycle until death by non-age related means.

     

  4. This one is pretty ridiculous, but is well documented and mathematically explained. The “Pistol Shrimp”, a small shrimp growing up to about 2 inches in length, compete with whales for “Loudest Sea Creature”. The shrimp snaps its claw to produce a “cavitation bubble”, which is a small bubble formed by intense pressure and immediately popped. As the bubble pops, it reaches temperatures of close to 5,000K (equivalently 4,727˚C or 8,540˚F) and releases a sound up to around 218 decibels (decibels are a unit of loudness, for comparison, a chainsaw is around 100 decibels, a gunshot around 140, and a space shuttle lift off is just under 200). The pressure of the bubble is sufficient to kill small fish.

    A pistol shrimp.

  5. This last one is my attempt to make this article relevant to Christmas. Did you know that, technically, Rudolf and the other reindeer were probably female? If we decide to forgo the fact that these reindeer were capable of flight and Rudolf had a bioluminescent nose, the Santa’s reindeer are depicted with antlers. Most male reindeer shed their antlers from November to December, and regrow them in the new year, whereas the females will retain their antlers over the winter until shedding them in the spring. I guess this last point barely counts; being a fact based on fiction…
  • http://www.facebook.com/profile.php?id=502581558 Tara Sud

    I really enjoyed this. Everytime I thought “oh I know where this is going” I was wrong and did infact know none of these facts about the animal kingdom!