Freethought & Rationalism Archive

WWSD · 03-13-2003, 04:30 PM

Quote:

Originally posted by Doubting Didymus
Its a bat, and that's just how many bats use their legs. I must admit I'm not entirely certain what DT is trying to say by posting it, however. Something to do with homology maybe?

I think it does have to do with the homology between the metacarpals of different mammals and how they've changed over time.

RufusAtticus · 03-13-2003, 08:31 PM

Doubting Didymus · 03-13-2003, 08:42 PM

Now THAT'S homology!

Happy Wonderer · 03-13-2003, 09:00 PM

Great!

Is there a version of this homology that has insertions marked to make the genes line up even more? (Is this a reasonable thing to do?) At least on chromo 1 and 9 it looks as if there is an insertion area on the human chromosone that pushes later bands out of line. If you accounted for that on the chimp (perhaps by a shaded blue area) then the tails would even more obviously line up.

(I'm thinking of a format somewhat like the "windiff" program for text...)

HW

Who has spent probably too much of his life comparing visual differences in code and data sets...

Answerer · 03-13-2003, 09:29 PM

Quote:

Originally posted by Magus55
Very very bad example of evolution. The bacteria gets "used" to the antibiotics and eventually becomes immune to it. Same concept as weight lifting. If you keep doing the same exercises over and over with no variation, your muscles will get used to the exercise and never increase.

That and evolution is a process of gradual change over long periods of time, not a couple days in your school bio lab.

Thanks for entertaining us.

:notworthy :notworthy

Oolon Colluphid · 03-14-2003, 02:13 AM

Quote:

Originally posted by Doubting Didymus
I must admit I'm not entirely certain what DT is trying to say by posting it, however. Something to do with homology maybe?

Sort of. Yes, ultimately it's about homology. But pictures can have a far stronger effect than words, almost visceral in some cases. You don't need to stare at chromosome banding patterns to 'get' the bat pic. As Starboy put it in the Keith thread, where I posted it before:

Quote:

This just SCREAMS evolution of forms. TOE may not be a completely accurate explanation of the emergence and variety of species but it has got creationism beat, unless of course you want to believe in a creator that likes to f*uck with our heads or has very limited imagination and ability.

I like it so much because it is so scarily human. We're familiar with our own skeletons, and you would have to be mad not to see how similar this is. Even creationists should (I hesitate to say 'do'

) know that much of evolution is about 'lengthening this', 'shortening that', and so on: variation of an existing pattern. That something so spookily recognisable is from something as different as a bat is, in a single picture, a wonderful piece of evidence for evolution.

IMO, of course

.

Cheers, DT

Treacle Worshipper · 03-14-2003, 03:42 AM

Quote Doubting Didymus
Its a bat, and that's just how many bats use their legs. I must admit I'm not entirely certain what DT is trying to say by posting it, however. Something to do with homology maybe?
Thanks, DD. I guess I was wondering why bats would evolve their legs at right angles. Does it give an advantage when hanging from ceilings, for instance?

DT, I see your point. It does look scarily like a "stretched" human. And it's a fantastic pic.
TW

Skydancer · 03-15-2003, 08:56 PM

Quote:

Originally posted by Treacle Worshipper
Quote Doubting Didymus
Its a bat, and that's just how many bats use their legs. I must admit I'm not entirely certain what DT is trying to say by posting it, however. Something to do with homology maybe?
Thanks, DD. I guess I was wondering why bats would evolve their legs at right angles. Does it give an advantage when hanging from ceilings, for instance?

DT, I see your point. It does look scarily like a "stretched" human. And it's a fantastic pic.
TW

The weird shape of the back legs is because they use those bones as anchors for the tail-wing membranes. (I never quite remember the technical term for them. Pyrgidium, or something like that.)

Harrumphrey · 03-16-2003, 09:05 PM

Quote:

Originally posted by Magus55
Very very bad example of evolution. The bacteria gets "used" to the antibiotics and eventually becomes immune to it. Same concept as weight lifting. If you keep doing the same exercises over and over with no variation, your muscles will get used to the exercise and never increase.

That and evolution is a process of gradual change over long periods of time, not a couple days in your school bio lab.

Wow, pretty low-order thinking there. I'd say late Pleistocene, and that's being generous.

Clutch · 03-17-2003, 06:08 AM

Magus' personal motto: "Ignorance is my greatest weapon."

Thread Tools	Search this Thread
Show Printable Version	Search this Thread: Advanced Search

03-13-2003, 08:31 PM	#32
RufusAtticus Veteran Member Join Date: Nov 2001 Location: NCSU Posts: 5,853

03-13-2003, 08:42 PM	#33
Doubting Didymus Veteran Member Join Date: Jul 2002 Location: East Coast. Australia. Posts: 5,455	Now THAT'S homology!

03-13-2003, 09:00 PM	#34
Happy Wonderer Veteran Join Date: Jan 2002 Location: Washington, the least religious state Posts: 5,334	Great! Is there a version of this homology that has insertions marked to make the genes line up even more? (Is this a reasonable thing to do?) At least on chromo 1 and 9 it looks as if there is an insertion area on the human chromosone that pushes later bands out of line. If you accounted for that on the chimp (perhaps by a shaded blue area) then the tails would even more obviously line up. (I'm thinking of a format somewhat like the "windiff" program for text...) HW Who has spent probably too much of his life comparing visual differences in code and data sets...

03-14-2003, 03:42 AM	#37
Treacle Worshipper Senior Member Join Date: Feb 2003 Location: Wales, UK Posts: 931	Quote Doubting Didymus Its a bat, and that's just how many bats use their legs. I must admit I'm not entirely certain what DT is trying to say by posting it, however. Something to do with homology maybe? Thanks, DD. I guess I was wondering why bats would evolve their legs at right angles. Does it give an advantage when hanging from ceilings, for instance? DT, I see your point. It does look scarily like a "stretched" human. And it's a fantastic pic. TW

03-17-2003, 06:08 AM	#40
Clutch Veteran Member Join Date: Oct 2001 Location: Canada Posts: 3,751	Magus' personal motto: "Ignorance is my greatest weapon."

Freethought & Rationalism Archive

The archives are read only.