From: Damien Broderick (d.broderick@english.unimelb.edu.au)
Date: Fri Jul 26 2002 - 00:36:25 MDT
At 05:40 PM 7/24/02 -0700, Robert wrote:
>> Why do humans age so slower than mice?
>Because all mammals evolved from creatures much smaller than mice
>and at every step of evolution where one selected for greater size
>(increasing survival odds) one had to also select for genetic programs
>that decreased the odds of single cells becoming cancerous.
Which led me to wonder how long the big dinos lived. A quick google didn't
get me very far, but
http://www.vertpaleo.org/jvp/19-654-665.html
comments that:
< Slow growth and additional deposition of accretionary lamellar bone
occurs in adulthood, and indicates attainment of maximum size in
Apatosaurus. All scapulae examined show cyclicity in vascularity indicative
of regular variation in speeds of osteogenesis. In contrast, Apatosaurus
radii and ulnae show consistent bone depositional rates throughout
ontogeny. Despite inter-element variability, all Apatosaurus bones sampled
corroborate the hypothesis of sustained rapid growth rates for most of
ontogeny, followed by gradual decline with attainment of maximum size.
Estimation of ages of similar to 10 years for large sub-adults refutes the
hypothesis that slow, indeterminate growth was required for Apatosaurus and
other sauropods to achieve extremely large body sizes. >
So maybe max 15-20 years? (But a site for kids suggests 100+ years..)
Damien Broderick
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