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How did Flight evolve in the animal kingdom ?


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Quote Capnrefsmat

 

Their wings would not cause them to fall and damage themselves,

as they would not be functional enough to fly under their own power.

 

End Quote

 

There seems to be a contradiction here or maybe you meant "would cause them to fall".

There is no contradiction.

 

The existence of wing-like structures does not mean the animal has evolved the behavior necessary to try to fly using them. Perhaps a tree-dwelling animal uses them as extra hands, and then as a parachute when falling from the tree, but has not yet evolved the behavior to try jumping off of things to fly.

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I think the way to visualize it is through logical steps of defending oneself.

 

(this is simplified a lot, but the point counts)

  • We "start" with creatures that are more fragile than many other predators; so they seek refuge above ground - like on trees.
  • The creatures that manage to avoid the predators more by going higher up the tree will survive and produce offspring that tend to do the same.
  • But as they hatch, the offspring sometimes fall off the tree -- either by winds, accidents, or when the predators shake the tree.
    Offspring that have mutations that help them *not* to die when hitting the ground live and produce offspring that tend to have the same mutations.
  • Initially, they will have some "partial" wing organ. While it won't get them to fly, flying isnt really its purpose. It will soften the fall and increase air-friction like a parachute. The offspring that have this mutation are more likely to live and reproduce offspring with the same mutation.
  • And as the time goes, offspring with *better* "parachutes" will be more likely to live and produce offspring with similar mutations, etc etc, improving their "parachute" to things like gliding-wings (like those of the gliding-snake and some types of flying monkeys), and eventually full-fledged flight.

This is extremely over-simplified. Also, as was mentioned before, wings were developed differently between some various species, so this doesn't represent the development of all wings. Still, it's easier to see how wings are very logical to occur from "no wing", and shows how there actually *is* a very good use for "half a wing", or a "partial" wing.

 

 

 

~mooey

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Edtharan

 

I liked the way you presented your information above. I have read it fully but need to study it a bit more to absorb some of your bat statistics regarding flight. I will look into the evolution of cats

and bats and some other things.

 

I am actually in the process of going through many of the resources shared by those above.

I am gratefull other contributors above took the time to share these links with me.

 

I have actually done more reading on the subject of evolution than many people here

know or understand, enough to understand things like natural selection, mutation

( chemical/carcinogen, radiation, enzymatic copying errors ), speciation and quite

a few other concepts ( have you heard of neural darwinism ?). I have seen the

geologic column which is quoted and presented in many places on the web

which gives one a time frame for what was happening evolution wise on the

earth in different periods over time.

 

I was having a discussion with Ophiolite the other day and he mentioned that

 

Quote from Ophiolite

 

The Earth is approximately 4.54 billion years old. The Late Heavy Bombardment Phase ended about 3.8 billion years ago. The first reasonable evidence of life is dated around 3.5 billion years, allowing 300 million years for life to arise.

 

End Quote

 

So it seems that from the initial formation of the earth 4.5 million years ago

(which I was already aware of) roughly 1 billion years elapsed

before the first forms of life that we are aware of arose.

 

I do actually understand how evolutionary theory states how life forms have changed

because of natural selection, mutation and speciation (I don't fully understand this

concept but I am looking into it. I think Dawkins says in one of his books

( Blind Watchmaker ) that generally speciation occurs in a geographically isolated

location where a subset of a major established population of individuals

splits off and travels to this new isolated location where the gene pool

diversifies ( specialises ?) and adapts to the environment of the new location

and so a new species can be formed in isolation from the originating population.

 

I comprehend what you are saying about hair length etc and wind resistance

reduction/ fall injury advantage in cats. It is still not clear to me that

this confers enough advantage to guarantee ( ahigher probability )

that more animals survive

a fall because of hair length and the other variables you mentioned.

I will look into it and get back to you on this.

 

Cats seem uncanny in their ability to mostly always land upright when they fall.

But I understand you are saying that this ability must have evolved/changed

like the other things you mentioned above. Again I need to look further into this.

 

Quote from Edtharan above

 

Over time, there has been a definite chain of advantages that

would allow natural variations in skin length, bone length and hair

length and patterns to allow a tree living mammal that hunts insects

to develop wings and flight with flapping.

 

You might think of this as "just a yarn", but the variations that have been

described would not be objectionable to any biologist (or anyone with even

basic knowledge of biology).and are all known to occur naturally in mammals,

including bats themselves.

 

End Quote

 

I must admit when I first read some of Richard Dawkins works that his arguments

didn't seem that water tight but now I will give them a second viewing

and find out what his arguments are based on.

 

I understand that the above variations you quote could have changed over

time but of course to most biologists ( who are also evolutionists )

these findings will be appealing. And I am not trying to insult/defame any

biologist or other scientist who uses the correct scientific methods

(about which I also know some things and will learn more).

 

Don't get me wrong. I am willing to study the scientific literature and this may

change my mind about many things (who knows ?).

I am working on it.

 

On the subject of bat evolution. Are you saying that bats before they

developed their proto wings were ground or tree dwelling creatures ?

If they as yet had no wings and dwelled in the trees then perhaps

this was where their food source was ?

 

Would it make any sense that a ground dwelling creature could develop

proto wings and garner some advantage from this ( again possibly food source ) ?

They crawled up there again.

 

I will concede that perhaps proto wings in bats could develop as you say above.

Again I have to look further into bat evolution.

 

Then there are other things like bat radar and turtles that can navigate

by the earths magnetic field and birds which probably do the same and

the list goes on ( and so the mind simply boggles and is awestruck

at all this complexity, but I digress).

 

Regarding the subject of strawmen, if I was/have been doing this here or above

it was unintentional (see your quote below).

Could you give me an example of where I have done this (from this thread)

or just give me an example of what you are talking about ?

 

Quote from Edtharan

 

First of all, you create strawmen not based on scientific literature

(which was pointed out does exist for your question, you just didn't seem to

read it) and then shoot down that strawman (which is what the strawman argument

is about). When it was pointed out your concept of evolution is wrong, you proceeded

to reject both the attempt to correct your misrepresentation and the literature that

was pointed out to help you understand it and get the right concept of evolution.

 

So, first step. Learn what the real theory of evolution is, and leave your strawman

version alone.

 

End Quote

 

And yes I need to learn how your quote facility works.

In the syntax below do I need to include the surrounding square brackets ?

 

[ quote name = "name" text /quote ]

 

Is there also a snippet function which works like copy and paste ?

 

I was a programmer for many years from the 1980s and am familiar with many

languages. I would be interested to get a copy of your evolution program

( can we organise this ? ). I think I could get my head around it

even if the language is new to me as with most languages many of

the principles are similar across languages/packages

( instructions, syntax and capabilities do vary ) and I have had to teach myself

new languages in the past. Will leave it with you.

 

Thanks for your enlightening discourse above.

 

Arete and anyone else who cares to comment

 

On arguments from incredulity. Am I wrong to be amazed and awestruck

by the awesome and complex chemical structure and functions of life ?

Don't most people feel this way when they are confronted

with the truth currently known about life ?

 

Incredulity is part of the wonder of life, being alive and experience of life fully.

 

I do of course realise that it is not a valid reason to base an argument on.

 

 

 

 

 

 

 

 

 

 

Mooeypoo

 

You make some good points above.

 

Your argument is quite logical and I am willing to concede that

wings could have developed this way which is of course

as per the above discussions only one way flight must have

arisen in the past out of many paths to flight in many

different creatures.

 

But I must admit that given my current knowledge

I must delve further into this to be fully convinced.

( am working on it).

 

Thanks again for your input.

 

Capnreffsmat

 

I understand what you are saying above that creatures with proto wings don't

necessarily have any flight behaviours yet and maybe their proto wings will confer

other advantages on the individual.

 

As to your other statment above and the/my perception of a contradiction

in what you said

 

Quote from Capnrefsmat

 

Their wings would not cause them to fall and damage themselves,

as they would not be functional enough to fly under their own power.

 

End Quote

 

I think I confused this as I thought on the one hand you were saying

proto wings would not cause them to fall and be damaged

because their proto wings would not be functional enough to fly

which didn't make sense to me and seemed to not be logical.

 

I now know (I hope) what you were saying.

They had proto wings which they were not yet using to try to fly

(they had not yet evo;ved any of those behaviours).

 

I think I am pretty clear on all you said now.

 

Thanks.

 

 

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You make some good points above.

 

Your argument is quite logical and I am willing to concede that

wings could have developed this way which is of course

as per the above discussions only one way flight must have

arisen in the past out of many paths to flight in many

different creatures.

 

But I must admit that given my current knowledge

I must delve further into this to be fully convinced.

( am working on it).

 

Thanks again for your input.

Sure, no problems.

 

If you want, I can find a few video demonstrations of how things work. Also, take into account that (a) my presentation was very much simplified, and (b) there *are* other ways for the wing to form, I just picked the one that seems to be the most readily logical.

 

If you need help finding resources let me know. Alternatively, if you encounter counter-arguments or any doubt about this or questions, tell us that too. We can see if we can answer.

 

Good luck,

 

mooey

 

 

 

P.S : In order to use quotes you can either click the "Quote" button at the end of each post, or write the tag [ quote ] whatever you want to quote here and you end with [ /quote ] <-- without the spaces inside the brackets.

That will make the quotes in a nice little box.

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Another thing on feathers and wings is that feathers probably originally developed as insulating materials not used for flying. Ratite birds are an example of this, but for lighter species this could allow them to jump higher or sort of glide because of the structure of feathers. This would allow them to both stay insulated and start on the path toward flight.

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Here's another form of wing-evolution, where the wing began as an assistance to climbing or walking an incline or jumping.

 

Even when we jump to a height, we tend to flail our hands around for balance, so the idea is that birds developed wings that started out as those "assistance" climbing organs.

 

Full explanation for this here (lots of pics and a video.. very nice):

http://www.people.ek.../554notes2.html

 

And this video by the BBC; I didn't watch it all, but I remember watching parts of it and I read the description. I looks very informative:

 

http://www.youtube.com/watch?v=JUIdarVPpsQ

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Mooeypoo

 

It is time for me to bite the bullet and fully apologise (which I do unreservedly)

for the things which I unfortunately said above.

 

I have been talking to Ophiolite and he showed me that my actions have

also insulted others here and the thread above

displays this to all above. I got off to a bad start and have not cast

myself in a good light to others here as well but only have myself to blame for that

(definitely the wrong thing to do).

 

My conduct above is an example of how not to proceed in an attempt to

communicate with others (very poor attempt on my part).

As such I am the one who stuck his metaphorical foot into his mouth

and so I am prepared to wear the consequences

of my actions. I deserve the fact that this thread is still up

(it could have been removed but probably serves well

as a reminder/warning of the consequences of this type of conduct).

 

A shame as the science discussion/content on this thread

has been very good/enlightening.

 

I am usually an effective communicator and do not normally go out

of my way to insult others where I can avoid it

BUT here I think I messed up badly and for some reason I was

too pushy and determined to get at the material/answers I wanted.

We all have biases and yes I have mine as well

(no excuse).

 

I can see you (and others) were only trying to get through to me but

I was pig headed and stubborn.

 

You are obviously very well educated and knowledgeable

( I will get back to you regarding your post on Radiometric Dating

on Earth Sciences). What I said was wrong and I regret saying what I did

and you obviously are an honest person.

 

So that's it basically. I will not make the same mistake again.

 

Thanks again for your forbearance/patience and very helpfull posts.

 

?8O)}

 

 

 

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I liked the way you presented your information above. I have read it fully but need to study it a bit more to absorb some of your bat statistics regarding flight. I will look into the evolution of cats

and bats and some other things.

I am more familiar with bat evolution than bird or insect. Not that I am a biologist (or even a scientist), it is just that happened to read more about it.

 

An interesting thing about Bat evolution is that they came from a shrew like creature. Shrews are small mammals that usually scurry around on the ground looking for insect and other invertebrates to eat.

 

This doesn't mean that shrews are an ancestor of bats, but that bats has an ancestor that filled the same niche as shrews, and shrews probably had the same ancestor as well.

 

If you look at the behaviour of modern shrews (and the behaviour can be determined from their skeletal structure to some degree), they rarely climb trees, but there are some that do climb trees. They live on the ground, and the ancestral bat (from fossils) would have also done this (climbing animals have slightly different leg and claw structures which are adapted from normal claws and legs to aid climbing).

 

Climbing would most like occur on low shrubs where falling is not too great a problem. This would enable the legs and claws of the proto-bat to adapt to climbing. Many insects and other invertebrates can live in such shrubs (eg: Caterpillars , preying mantis, flies, dragonflies, etc) and thus provide the adventurous proto-bats with an extra food source (an advantage).

 

Of course, you also get medium sized shrubs that are more like short trees, and this provides a gradual increase in height that these animals can adapt to exploit. The higher they go, the more they need to develop protection from falling. But, as there is a gradual increase in heights that they can go to, they can keep pushing higher and the advantage that gives allows the gradual transition from simple structures to the more complex, fully developed ones.

 

This means it is not a case where they lived on the ground, and then lived in the tops of trees, the continuum of heights of shrubs, to low trees, to medium trees, etc means that at no point was there necessary for there to be a sudden jump from flightlessness to fully fledged flight capabilities.

 

I was having a discussion with Ophiolite the other day and he mentioned that

 

Quote from Ophiolite

 

The Earth is approximately 4.54 billion years old. The Late Heavy Bombardment Phase ended about 3.8 billion years ago. The first reasonable evidence of life is dated around 3.5 billion years, allowing 300 million years for life to arise.

 

End Quote

 

So it seems that from the initial formation of the earth 4.5 million years ago

(which I was already aware of) roughly 1 billion years elapsed

before the first forms of life that we are aware of arose.

the origin of life (Abiogenisis) is not the same as Evolution. Evolution deals with how organisms change over time, Abiogenisisdeals with how those organisms developed from simple chemicals. The origin of life is more about chemistry and thermodynamics than biology.

 

Cats seem uncanny in their ability to mostly always land upright when they fall.

But I understand you are saying that this ability must have evolved/changed

like the other things you mentioned above. Again I need to look further into this.

Yes, they do. But you must remember their ability is the result of hundreds of thousands of years (perhaps millions of years) of evolution. It might seem uncanny now, but it didn't start off that way.

 

I must admit when I first read some of Richard Dawkins works that his arguments

didn't seem that water tight but now I will give them a second viewing

and find out what his arguments are based on.

Yes, the reason that they might not seem water tight is that they were simplified so as not to get bogged down in the details. If he did work to make them water tight, then the books he writes on evolution would take up shelves in a library.

 

There are just so many details from the evidence gathered that it could take a lifetime just to go though them all (and more are being discovered all the time too).

 

With that much attention to detail, the reader would get bored before Dawkins could make his point. So, he had to compromise by giving a simple description in the main body of the book, but then uses references at the end to point to where the reader can get that information for themselves.

 

I understand that the above variations you quote could have changed over

time but of course to most biologists ( who are also evolutionists )

these findings will be appealing. And I am not trying to insult/defame any

biologist or other scientist who uses the correct scientific methods

(about which I also know some things and will learn more).

If evolutionary theory states that for a shrew like mammal to develop into a bat through evolution would require certain changes to occur, then when fossils are discovered that match those changes from the ancestor species to modern bats, then that is pretty good evidence to support the theory. The theory makes a prediction and then is confirmed by observation.

 

On the subject of bat evolution. Are you saying that bats before they

developed their proto wings were ground or tree dwelling creatures ?

If they as yet had no wings and dwelled in the trees then perhaps

this was where their food source was ?

Bats would have developed mechanisms to survive falls due to their behaviours taking them up into the trees and shrubs. This could have been for many reasons (eg: after food, to escape from predators, living space, etc). But, remember, they wouldn't have just gone from a ground living species to living in the tops of trees. there would have been shrubs, smaller trees, and so on up to the point where full flying capabilities would have been an advantage.

 

Would it make any sense that a ground dwelling creature could develop

proto wings and garner some advantage from this ( again possibly food source ) ?

They crawled up there again.

The proto-wings would have developed as a result of them moving up into the trees. Evolution doesn't deciding what an organism should have before the need it. Evolution works in response to the need. So until they moved up into the trees they would not have needed proto-wings.

 

I will concede that perhaps proto wings in bats could develop as you say above.

Again I have to look further into bat evolution.

It is surprisingly quite interesting how bats evolved.

 

Then there are other things like bat radar and turtles that can navigate

by the earths magnetic field and birds which probably do the same and

the list goes on ( and so the mind simply boggles and is awestruck

at all this complexity, but I digress).

Yes, there are many such structures and organs that boggle the mind. However, there are clear, step by step pathways where each step confers some kind of survival/breeding advantage to the organism.

 

Bat sonar is one. Shrews make high pitched chirping sounds (some about the same frequencies as bat sonar calls - smaller animals tend to make higher pitched noises). Now, it is possible to hear the return sound (the echo) from these kinds of calls.

 

You can actually learn to do it yourself. You can learn to navigate by making clicking sounds (there are people who can do this with their mouth, or you can just buy a toy that makes a clicking sound) and listening for the echo. It takes a bit of practice, but it is not hard to learn the basics of it.

 

So, if the ancestors of bats lived in dark places, or hunted at night (more insects are out at night and less predators are out at night too), then using clicks and listening to the echo would be a good way to navigate (even for a ground living proto-bat). As this confers a survival advantage (know where you are and detecting prey), then evolution can act to refine this more and more, thus leading to full bat sonar capabilities.

 

I was a programmer for many years from the 1980s and am familiar with many

languages. I would be interested to get a copy of your evolution program

( can we organise this ? ). I think I could get my head around it

even if the language is new to me as with most languages many of

the principles are similar across languages/packages

( instructions, syntax and capabilities do vary ) and I have had to teach myself

new languages in the past. Will leave it with you.

The basic algorithm is this:

1) Create many data set copies from a few original data sets

2) While making these copies add in small variation (mutations)

3) Test these new data sets against a set of criteria

4) Repeat until no data sets are left, or the user indicates to stop.

 

Look up Genetic Algorithms: http://en.wikipedia.org/wiki/Genetic_algorithms

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