Re: sup guys, need help on Evolution
Reply #3 - December 06, 2011, 09:36 PM
I am not a scientist either, so there may be some errors, but you may wish to look into this as below.
1. The functions of body parts change and adapt. A limb originally used to walk on land that now is used to propel an animal through water (ie in sea mammals, whales etc) would have resulted in many adaptations, where the transitional form may well have been able to do both partially, but perhaps not as well as either Pure Fin or Pure Limb, such an animal (ie the precursor to the whale) may well have lived both in AND out of water, enabling it to take advantage of both land and water based resources (ie food) and escape water-based predators by moving to land, and land based predators by escaping into the water, thus helping it to survive. A fin that evolved from a limb would not be the same as a fin that had only ever evolved to live in the water, but its function has changed. Evolution will tinker with (adapt) already existing bodily structures, but cannot start afresh and 'invent' a totally new structure. So although a half limb/half fin may not have its original function, its function will change to fit its new environment, with each slight step conferring a survival advantage.
There are manymany other examples living today of animals with partially adapted body parts where the funtion has changed.
Penguins have "half-wings/half flippers", and they have not become so vulnerable that their "survivability is zero"
Seals cant move on land very well, but enough to survive and get by (escaping killer whales), but put them in the water and they go like shit off a shovel!!
In evolution Necessity is the Mother of Invention.
(or to put it slightly better "Desire of individuals in a population to Survive in their Environment is the Mother of Adaptation within that population over time")
Whales (and dolphins etc) live in the water like fish, but UNLIKE fish, their spines bend up and down, not side to side like fish. This is a clue to their recent land-based mammalian ancestry. A whales tail is also horizontal, where a fishes is vertical for similar reasons. Not to mention the other obvious differences that whales have lungs and fish have gills. Whales give birth to live young, fish lay eggs etc
When that guy says that the survivablity of such animals is ZERO he is talking bollocks cos whales really do exist!!! Hahaha
You may also wish to research Vestigial Structures which are body parts that have all but disappeared, leaving a few remnants behind. Whales have vestigial rear limbs. Kiwis have vestigial wings.
Not sure if this answers your question.
Please do NOT take MY word for this. These are just starting points for you to research yourself.
Can I recommend Richard Dawkins book, The Greatest Show on Earth
Or
Jerry Coyne's book Why Evolution is True.
Both are excellent books which are geared towards the non-scientist man in the street like me. If I can understand them they MUST be good books. :-)
I am better than your god......and so are you.
"Is the man who buys a magic rock, really more gullible than the man who buys an invisible magic rock?.......,...... At least the first guy has a rock!"
Topic: sup guys, need help on Evolution