Unfortunately, I originally forgot to close the quote mark at the end. Sorry ’bout that. But generally I stand by what was said.

Your assertion that “… evolution only gives the apperarance of trying to go in a smart direction but really it could stump itself and create a species that is only attracted to the prettiest but most burdened members rather that the best survivors, and actually wipe itself out.” is a generalisation that could be proved for some species, but I feel the vast majority just gets on with trying to exist, you know, where’s the next meal coming from? There are symbiotic relationships across most of the Life-forms, some highly unlikely, Others rely on good seasons, where there is abundant food available, meaning that somebody had an easier time for a while. It seems that an inbuilt control mechanism obtains. I think Human-kind is starting to realise this and recognises that there is no free lunch, because it has to be paid for somewhere, somehow, and sometime, eventually.

We tend to not appreciate the timescales involved, or imagine that they all have the same duration, and that the effects are all equal. A small variation in food supply for one creature, may have dire consequences up the food chain. A snake can exist for a month on one decent meal, it managed to catch. I reckon the next day if another suitable meal came along it would have it for desert, and not say “Nah, I’ve already dined this month”. No, it would try to eat as much as it could, and the left-overs would provide a meal for some other scavenger. I grant there are probably as many scenarios as species.

Ivan.

It’s a good point but i’m not sure.. I think there doesn’t need to be ANY underlying adavntage of the pretty tail. There could even be a strong disadvantage. Remember, evolution only gives the apperarance of trying to go in a smart direction but really it could stump itself and create a species that is only attracted to the prettiest but most burdened members rather that the best survivors, and actually wipe itself out. I’d be interested to know if this kind of thing happens…

Liam

I suggest it may be a “Boy named Sue” syndrome. (Remember the Johnny Cash record way back when?) If you had to battle for existence, but also needed to carry a huge colorful decoration almost all the time, a la the name “Sue”, ( no reflection on all the Sues in the world), then you would be the better fighter. If not, the genes would not get passed on. Simple as that.

That there is a Lyrebird means that tactic worked at least. With the environment varying over the centuries, some changes take much longer to happen. What use is the human appendix? Or the residual back legs of the whale? They (the legs) have almost disappeared, but not quite in some species. It is the hidden advantage that is important.

Ivan.

The way i think it really works is that it just does.. The tail, singinig ability, etc, is indicitave of nothing, but is nevertheless attractive to the opposite sex. once such a system gets going the females who are most attracted to pretty tails mate with the males who have the prettiest of the pretty tails and produce male babies with the prettiest tails and female babies most inclined to be attracted to pretty tails.

Yes, that is a description of sexual selection. However, the missing element is that prettier tails are presumed to make the peacock easier for predators to spot, and harder for them to escape. Different selection pressures work against the big tails. So how come the big tails win out, despite being a disadvantage? That is the point of understanding how it makes the animal more successful.

I dont think you need to find a reason that the trait makes the animal more sucessful for an explaination of why it happens.

I’ve always thought the idea that species are attracted to indicators such as the peacocks tail beacause they reveal underlying genetic survival ability must be mistaken. Surely such a system would breakdown quickly as peacocks with bad survival ability happened to learn to grow pretty tails and all of a sudden had loads of bad-surviving-babies.

The way i think it really works is that it just does.. The tail, singinig ability, etc, is indicitave of nothing, but is nevertheless attractive to the opposite sex. once such a system gets going the females who are most attracted to pretty tails mate with the males who have the prettiest of the pretty tails and produce male babies with the prettiest tails and female babies most inclined to be attracted to pretty tails.

I know it sounds like a bit of a circular argument and doesnt answer the question of how it starts. But leaving that aside it is clear that sexual selection like this can push evolution in a strange, pointless direction and produce starteling abilities (impersonation) or colours with no survival purpose other that attraction.

Also I’m not saying this is the case with the lyre bird, just pointing out it’s not necessarily necessary to search for a survival value to explain it’s ability.

Liam

My grandmother once had a mockingbird here in the US imitating what she was playing on the piano, which confused her at first until she figured it out. For the most part, the mockingbirds outside my window go through a non-stop program of over 20 songs. Apparently they can mimic over 200 different bird songs.

Overweight, cheeto-eating, and video-game-playing are not uniquely indicative of financial stability. Sometimes they’re lazy sponges off their parents. And it doesn’t indicate ability to care for the young, or interest in providing for the family, but selfishness – provide for their own interests.

Then there’s the social interaction issue.

If you see this, what part of rural Ga.? Just curious as southeast Ga. has been my stompin’ grounds for the vast majority of my 47 years.

And, I’m also a HUGE Attenborough fan. The original comment attributing him to the video clip was mine.

I hope he hasn’t been lying to me all these years!

[Nice to see no one made reference to burning pants ;} ]

So the ability to mimic other birds is an essential trait of many, if not all songbirds, but it is generally limited to a critical period during childhood. Thus the more robust, long-term learning ability may represent an issue where the learning period is extended indefinately. Maintanence of traits into adulthood that are normally restricted to childhood is an important evolutionary tool that has proved critical many times. So that would explain how such an ability came about, but not why it is useful.

My guess it is may have evolved in species that need to be highly adaptable. Note that parrots, with probably the most variable communication capability, also are most likely the most intelligent group of birds as well. Which led to which I do not know, and they may not be related at all, but it would make sense that a highly intelligent, highly social group of birds would tend to evolve a sophisticated communication system. It is the same with primates.

The ability to produce a wide variety of songs and learn them continuously throughout ones life may be correlated with the ability to adapt to changing environments in general, so females that were attracted to males with variable songs may have had a selective advantage in that they were also attracted to males who were able to adapt to environmental changes. This would then put selective pressure on the males to develop more sophisticated songs to impress the females.

For instance, rooster combs’ size and redness are correlated with health, therefor females who are attracted to males with big, red combs are, by extension, attracted to fit males. Many things that animals are attracted to are not so much selective advantages themselves, they are correlated with advantageous traits that are not readily visible. Therefor being attracted to the useless trait means also being attracted to the undetectable useful one. That would be my guess on the issue.

Best regards!

But the chainsaw… now THERE’S an achievement.

I suspect an ID adherent would see the lyrebird as one more proof of God’s infinite imagination: something “too complex” to have arisen without a creator.

… it’s a bird! I saw this over on Bad Astronomy and had to write it up here. It’s a video of an Australian lyrebird, and the bird’s ability to mimic sounds – even man-made sounds, is remarkable. I would…

They have recently learnt how to do mobile phone ringtones as well..

I hope they’re not doing the Crazy Frog, or they might soon face extinction…

I bought myself a liarbird
He came with free drinks just to blur
The lies falling out like rain
On an average English summer’s afternoon
I bought myself a new notebook
Sharpened my guitar and went to look
If this biz was just as bongo as the liarbird made out
All he would say
Is “I can make you famous”
All he would say
All he would say
“Just like a household name” is
All he would say
Methinks world is for you
Made of what you believe
If it’s false or if it’s true
You can read it in your bible
Or on the back of this record sleeve
I bought myself a liarbird
Things got more and more absurd
It changed to a cuckoo
And expanded filling up with all I gave
I bought myself a big mistake
He grew too greedy, bough will break
And then we will find that liarbirds
Are really flightless on their own
All he would say
Is “I can make you famous”
All he would say
All he would say
“Just like a household name” is
All he would say
Methinks world is for you
There’s no handing it back
If it’s false or it’s true
You can read it in your prayer book
Or on the side of a cornflake pack
I gave away a liarbird
A couple less drinks and now I’ve heard
The truth shining out like sun
On an average English winter’s afternoon