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Re: origin of bats/suspect trees?





> 
>   As for replicating morphology, this is actually not true. There are enough 
> genes who relevant to a morphological suite are known, such as sonic 
> hedgehog, 
> which is perfectly capable of being mapped onto a morphological tree to 
> consider 
> its effect. You can constrain one morph data set to agree with a mol one, and 
> map a character or gene appearance and determine compatability. Not that this 
> is 
> hard.

You're slipping back into DNA-land.
> 
> 
> 
>   I cannot see how this deserves much, if any comment, other than that 
> morphology more often than not a product of genes, not the other way around.
> 
True. But genes are funny. 



> 
> Where's the suite Jaime?>
> 
>   While David is correct in averring that manatees has rounded, oblate ribs, 
> my 
> argument arose through comparative suites of features. There were comments 
> which 
> were brought up about correlative features, such as elongated 
> forelimbs/elongated hindlimbs, elongated metatarsals and an elongated 
> calcaneal 
> heel. Lower down I mention teeth, and this is even more securely true, and I 
> even mentioned sloths as an example of this, despite their differences.

Jaime, you can name teeth. Dorsal fins. Unguals. All good and worthy, but you 
must put them all together and test them as a whole. When you do, you'll see. 
And I know I'm preaching to the choir.

It's like I'm an astronomer and I find a new star. I tell other astronomers to 
point their telescopes at that star and look for themselves. All I'm doing is 
showing you new taxa to consider. If you want to look at those new taxa in a 
new light, you'll know that someone else has pioneered the way and you can test 
the hypothesis. If you find it valid, great. If you find objections, please 
report them -- but _after_ you've done your analysis. 
> 
>   Moreover, different animals in similar habitats have similar physiologies, 
> indicating that we can take a feature or suite of features and note that 
> these 
> are related to that behavior; there are features tied to fossoriality, 
> arboreality, cursoriality, perching, brachiating, suspensoriality, 
> opposability 
> of the hallux/pollex, etc.
> 
> Sharks and dolphins both have a suite of convergent characters, but a larger 
> number of characters that ally them with their proper clades. That's the same 
> here. You can bring up this character and that, but tie together 150+ 
> characters and then get back to me.
> 
>   Irrelevant. You don't think a constraint in habitat like suspension would 
> promote elongation of the phalangeal proportions, as it does in brachiating 
> apes? If not, then there should be even less reason why animals that do not 
> use 
> the fingers for propuslion should ever have such digital proportions. Bats do 
> not possess the pedal proportions of brachiators, meaning that walking around 
> on 
> their feet upside down is not a behavior they engage in in any regular 
> past-time. 

But do bats have the pedal proportions equivalent to the manual proportions of 
brachiators such as gibbons? I can't recall at present. But then bats are 
passive inverts. Like sloths they let their claws do the work. 

They do not, they lack such proportions, and thus one might expect 
> they lack such constraints any so-called "terrestrial bipeds" possess.
> 
> 
> the whole critter.>
> 
>   Which is why I mentioned diet. Look at predators: dental anatomy must be 
> suited to rendering prey, the animal must be capable of processing 
> proteinaceous 
> material, and the animal must have the energetic regime to acquire the prey 
> in 
> the fIrst place. Finding a ziphodont crown can tell us that the animal is 
> suited 
> to cutting flesh. If that crown had denticulations, we would expect the prey 
> item to possess possible muscular tissue, and likely be vertebrate in nature. 
> Possession of a jaw full of ziphodont teeth tell you the animal is a strict 
> carnivore. If the dentition is heterodont, with molariform or incisiform 
> teeth, 
> then we can expect the diet to vary, and can expect there to be more 
> generalistic features of the body. This is what you can expect from a single 
> tooth. And that's just the apex of the crown.

I think you'll find the outgroups I have proposed for bats to have a fairly 
cosmopolitan diet, as would be expected because bats likewise vary widely, but 
chiefly fruit and insects.
> 
>   Different animals with different evolutionary histories will convergently 
> acquire the same dental features given the same dietary avenues.

True.

Best to you, DP
> 
>   Cheers,
> 
>   Jaime A. Headden