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The beginning of humans

  1. Nov 18, 2009 #1
    Children are incapable of fending for themselves. It seems most insects and animals are hard-wired for survival at their birth/creation. Human babies are completely defenseless. This would seem to point to the fact that the first humans could not have been children or would have needed a caretaker. Does evolution destroy this idea?
  2. jcsd
  3. Nov 18, 2009 #2


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    The problem is your desire to put a stake in the ground and declare some small group of individual animals as "the first humans." Life doesn't work that way.

    - Warren
  4. Nov 18, 2009 #3
    The offspring of many species are incapable of fending by themselves. I really cant think of any mammal whose offspring is not defenseless after birth, and does not need a period (longer of shorter)of care.

    Some species are even more exposed, for example think at fishes who lay eggs which are fertilized externally, than left to chance. Most of those eggs are simply destroyed. Evolution compensate for this with the enormous egg count deployed by fish females.

    Well, whatever gave birth to you, cared for you :P We usually call her "mommy". I bet we still thought at her this way back in the good old days, even if she was an ugly ape :P
  5. Nov 19, 2009 #4
    One could state that human mammals evolved to cry when they get hungry to signal their parents to feed them. Those that lacked this crying mechanism would have died of hunger!
  6. Nov 19, 2009 #5


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    Dan P has stated it well. Human infants are actually quite a bit better off than some other altricial species. Altricial is the term used for animals born in a more undeveloped state that require a lot of parental care to survive because they cannot fend for themselves. The opposite of altricial is precocial, those that can care for themselves at birth or very soon after. Take, for example, rats or birds, that are born naked (i.e., no fur, hair or feathers) and blind. Or, what about kangaroos that are born very undeveloped and finish developing in the mother's pouch?

    Species that are altricial require a lot of parental investment. More precocious species can just be abandoned as eggs or soon after birth. Mammals are often (but not always) altricial species, because live birth as opposed to egg laying enforces an upper limit on development before a baby is too large to squeeze through the mother's pelvis to be born.
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