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Naked mole rats and the paper of Ruben et al (1996)



It's nice to see you bone gazers going at each other throats, instead to 
some poor astronomer's. You are too emotional though.

I deleted the post and I can't remember who posted it, but it was 
something about what we could infer from the presence or lack of RT's 
in naked mole rats, those disgusting ugly little creatures.

Even if naked mole rats (NMR) have RT's that doesn't mean much unless
NRM are bradymetabolic ectotherms, the point made in the article is 
that RT's and large aerobic capacity are connected with tachymetabolism.
That's their working basis. They should have been more careful with the
terminology; by the way they name one of the groups as reptiles and put
birds on the other, this seems a job to our friend the cladistic
assassin!!! 

About the connection between RT's and tachymetabolism, and since I 
won't be able to get the references on the subject in the immediate
future, can anyone answer to the following questions (here at the
observatory the only non-Astronomy journals I gen get my hands on are
things like Science):

  - How do the water savings associated with RT's correlate with mass?
  - What fraction of the nasal cross-section is used by RT's?

The first question comes from the fact that the water gains associated
with RT's in some of the examples given at list seem only marginally
important, couldn't they be a result of the miniaturization of the
ancestors of today mammals and birds? By the way are mammalian RT's
all equivalent (placental, marsupial and monetremes)?

The second question is to try to understand if Ruben et al's (1996)
sample of  "reptiles" is valid or not. Above 10 kg their sample consists
mainly of crocodilians (only one monitor lizard the rest are alligators
and crocodiles). Now why would crocodiles (aquatic creatures) need to
save water? Unless the RT's don't use much of the nasal passage the
differences shown are irrelevant. Of course I believe the authors
in Ruben et al's (1996) paper considered this question yet I would like
someone to clarify it, I would like to firmly establish that big nasal
cross-section is required to tachymetabolism and not just a requiremnt
to have RT's.

I will be posting something on my objections to the sample used in 
Ruben et al's article if I receive some input to this post.

Dalmiro Maia