12 Nov '14 13:53>
Lesson 1: Thread 161600
Lesson 2: Evolution is a gradual process.
It's not: monkey -> monkey -> monkey -> human. The progeny is always the same species as the progenitor(s). Dawkins gave an excellent analogy using age. It's not that you go to bed in the evening and in the morning you're old. It's a smooth, hardly noticable process of change from hour to hour, and then years later you realise you're in a very different body from how it used to be; you're old. Speciation is also a smooth, hardly noticable process on the surface, and then one day the difference between the original population and the latest is so big, that you in fact have a new species.
Now, you might argue that if it's so slow and gradual, how can we know it's really happening, and what a good question that is too.
Just as age is eventually evident, so is speciation evident after the fact. If we leave the fossil record, homology, vestigial organs and the like aside, perhaps the best evidence is the genome. If you take your children's DNA and compare them, you will find ever so slight changes in them, yet it will be obvious they are not one and the same, and they share parents. You can do this to figure out that a bunch of cousins have the same grandad, and that a bunch of people have a common ancestor from europe, or africa.
Now, when we look at different species and the exact same kind of evidence points to the exact same conclusion, logic dictates that we must follow this evidence where it leads: to accept common descent for all living things.
As we learned in lesson 1, this claim is falsifiable. Find a species whose DNA doesn't appear to fit the hierarchial nature of things, and evolution is a bust.
Lesson 2: Evolution is a gradual process.
It's not: monkey -> monkey -> monkey -> human. The progeny is always the same species as the progenitor(s). Dawkins gave an excellent analogy using age. It's not that you go to bed in the evening and in the morning you're old. It's a smooth, hardly noticable process of change from hour to hour, and then years later you realise you're in a very different body from how it used to be; you're old. Speciation is also a smooth, hardly noticable process on the surface, and then one day the difference between the original population and the latest is so big, that you in fact have a new species.
Now, you might argue that if it's so slow and gradual, how can we know it's really happening, and what a good question that is too.
Just as age is eventually evident, so is speciation evident after the fact. If we leave the fossil record, homology, vestigial organs and the like aside, perhaps the best evidence is the genome. If you take your children's DNA and compare them, you will find ever so slight changes in them, yet it will be obvious they are not one and the same, and they share parents. You can do this to figure out that a bunch of cousins have the same grandad, and that a bunch of people have a common ancestor from europe, or africa.
Now, when we look at different species and the exact same kind of evidence points to the exact same conclusion, logic dictates that we must follow this evidence where it leads: to accept common descent for all living things.
As we learned in lesson 1, this claim is falsifiable. Find a species whose DNA doesn't appear to fit the hierarchial nature of things, and evolution is a bust.