Keith

Reached a point of utility? Advantage for who, or what? If nature is devoid of purpose, then speaking of utility is incoherent. I'm making this observation from your point of view; not mine. From my point of view it makes perfect sense to speak of utility, function, design, and purpose in the things that nature "makes."

Keith

nogods4me

advantage to the organism that got the trait, and by advantage, I just mean that it made it more likely to reproduce. perhaps only slightly, but an advantage nonetheless.

I am still confused over your questions concerning the ears of bats, or more properly I guess the development of echolocation. I get the impression that you think that all these little bits of the ear evolved for thousands of generations independant of one another and they just happened to fit together to create the bat's ear and its ability to echolocate. or rather, that you think that is what we think. Am I reading you correctly?

Keith

How do you know that the vast majority of species become extinct? If this is true, then one explanation is that a species that fails to adequately anticipate its future survival needs will not survive. So, if what you're saying is true, how do you explain that some species have survived even beyond a few thousand generations? Why are some species better than others at predicting the future and preparing themselves for it?

Keith

Keith

Sort of. I'm saying that it doesn't make any sense that the individual ear parts could all have developed independently of each other. If it was done independently, then it would be miraculous for the same reason that 300 monkeys might independently write equal-sized sections of the London phone book resulting in a complete, and exact copy of the LPB.

Keith

cricket

They're not predicting and preparing; they're. just. better.

They happen to have what it takes to survive.

Later, if there are environmental changes, they may or may not.

Can it really be so difficult to understand this?

Starboy

Keith, are you thinking about this in any way at all? Let's take a well known instance, the dinasours. Are you saying that they knew a large object would hit the earth and radically change the environment and decided to do nothing about it and that is why they are extinct? Keith, do you have any idea how wierd your ideas are? Have you given them any thought at all?

Starboy

Happy Wonderer

Could you back up your assertion that "if nature is devoid of purpose, speaking of utility is incoherent?"

Advantage is for an individual (which is why I said "you"), not for "Nature" or "bat kind." If an individual would gain no reproductive benefit from improving a function, there is no reason to expect to see that function improve in the general population.

When everybody "sees" well enough to detect any posible prey, then better "seeing" bats are no more likely to reproduce than the average bat. This is what I mean by "seeing" reaching a certain point of utility. We can use other words if you like, but I think my point is clear.


HW

Salmon of Doubt

If you'd like some information on mass extinctions, the main one was in the early Permian, where 58% of tetrapod families became extinct. And I'm not talking species, I'm talking families. An example of a family is the Felidae, including all big cats and domestic cats, or the family Equidae, including the various species of horses, and zebras. Other mass extinctions include the loss of 49% of tetrapod families in the early Triassic, 22% in the late Triassic, and 14% in the late Cretaceous (the one that wiped out most dinosaurs except the birds).

If 'anticipation' and 'prediction' came into this at all, surely the families involved should have realised that they were about to be made extinct, and all the individuals would have just laid down and died, or not bothered to reproduce.

But because we're talking about RANDOM events here, this doesn't come in to it at all. The families that died just happened to be ill adapted to the conditions when they suddenly changed, so they died.

The ear parts DIDN'T evolve independently! They were all evolving at the same time, and if certain relative sizes of ear parts happened to make an individual hear better, then the animal found more food.

This has been explained already several times by different people. Do you really not understand what we are saying? Or are you being deliberately obtuse and consistently misunderstanding things to get more people to argue?

Happy Wonderer

Here is the basic problem. You are (probably for rhetorical purposes) ignoring the basic unit of evolution -- which is the individual.

How do improved features appear in a population? Do all the bats wake up one day with slightly improved ear bones? (OK guys, download your new upgrade!) Do all the bats give birth to new-improved kids when an improvement is ready? Of course not!

An individual bat is born with a slight improvement. It is perhaps slightly better able at catching prey than its peers and thus this bat is slightly more resistant to the 'starvation' sieve. If the insect population crashes, this bat is more likely to survive than its peers. Thus it has individual offspring. The next time the insect population crashes, these offspring are not only more likely to survive, but the 'unimproved' offspring are now even less able to survive: the improved guys are getting all the bugs. Continue long enough and all you have are the improved guys.

If a bat is born with an 'improvement' that 'outpaces' the ear system, then that individual bat is toast. (Yuck! Bat Toast!) We would call that a "birth defect." It has no impact on the general population other than that there is one less bat competing for insects. It is only those individuals that have improved ability to reproduce that affect the future characteristics of the population.
HW

Some Loser

I never said I did. Reread my previous post and try again.