Saturday, November 6, 2010

Analogy/Homology


  Homologus Traits
  a.  Scorpions + Spiders = Shared Homologus Traits

b.     Scorpions and spiders are both are very similar and different from each other.  Spiders catch their prey in either webs or by hunting on the ground for insects and beetles throughout the day.   Scorpions on the other hand are unable to see very well, so they reside during the day in cool places under rocks or in burrows and only at night are they able to hunt for food; digesting their food in liquid form.  Both spiders and scorpions develop three stages of growth throughout their life.  Spiders begin as an egg, then the nymph, and last an adult.  Scorpions experience molting stages throughout their lifetime.  Even though these two species have different lifestyles and look completely different they both share common traits.  Both spiders and scorpions share resemblance in their abdomen and the cephalothorax.  They also both have 8 legs, which is sought out to be one of scariest traits to possess!
c.     Both the spider and scorpion share a common ancestor.  They both are classified as arachnids.  They are not considered insects because they do not have antennae or wings.  They possess an exoskeleton and an internal structure of cartilage, which certain muscle groups are attached!


Analogous Traits

      a.  Platypus vs. Duck  
b.     The platypus and duck both share some similarities.  Both the duck and platypus have bills, in which they both use to dabble through mud to find food.  They also both nest and lay eggs!  Which is surprising because the platypus is not related to the duck at all.  The platypus is considered a mammal, yet mammals are usually considered to give live births.  The reason why the platypus lays eggs is because it does not have a placenta.  A duck however is not a mammal, and is instead    classified as part of the bird group.
      c.  Birds descended from dinosaurs, which is interesting because I was reading an article and they found a dinosaur in China with feathers!  My dad is a geologist and actually has a friend who is a paleontologist and they are studying chickens’ and ducks’ behaviors and personalities to get a better insight into dinosaurs’ personalities.  Scientist have also discovered that the “scary” T-Rex that Hollywood portrayed as being such a frightful monster is actually a scavenger and couldn’t even run fast.  Besides all this dinosaur talk, platypus is considered a mammal, which is entirely different then a bird.  So, that is why the platypus and ducks have analogous traits










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