Re: Babies and Ecology

[Richard W Travsky <rtravsky@uwyo.edu>]

On Mon, 2 Oct 2000, Emily Tremain wrote:
> >I don't know about Tyrannosaurs, but didn't Bakker find some evidence of
> parental feeding of infants in ceratosaurs (from the Jurassic of Wyoming)??  
> 
> Yes. I just heard Bakker lecture at St. John's University in MN and he
> discussed evidence of parental care for infants. The lecture was less
> technical in nature; he didn't even give the names of the dinosaurs
> involved. It sounded as though he had found evidence of _Allosaurus_ teeth
> marks, both adult and infant, on the distal end of a sauropod femur. (maybe
> it was _Ceratosaurus_?) He said that he had found at least 4 isolated sites
> in which this pathology was observed. He showed some slides of this femur,
> and moved on to another topic. I had to leave immediately after the
> lecture, so I didn't get the chance to ask about it. Hopefully this scrappy
> information will be of some use....

Perhaps I can shed some light on that. Baker spoke here at the University
of Wyoming last last year and I posted a summary to this list.

Here's the relevant extract:


Regarding predators, he said he'd been looking for baby
teeth for years. Age can be discerned from shed teeth.
He said he's such teeth. The slide(s) showed these
such a tooth on the end of a match stick. These were 
tiny teeth. In fact, he's found 35 of them at this
site. Basically, it's a nursery. There are remains
of 30 different animals (species?) here. The bones
have been nibbled on. The slides showed tiny gnaw marks,
no doubt made by the young.

In fact, the bones show both tiny and large gnaw marks.
This indicates the parents also chewed on the bones.
It seems, just like with bullets and a gun, the gnaw
marks are distinctive.

The bones at the "nursery" included preator bones. The
idea is that in a warm, tropical climate, meat rots
before long, attracting other predators. And then it
would seem the parents have something to say about it.

Also, adult teeth, of the same species as the baby teeth,
were found in the same site.

I don't recall that the species of predator was specified.

Summary: a high level of predator parenting.

After the talk I asked if the finds at this "nursery"
represented one breeding season. He thinks so. There
are two events where flooding apparently covered the
site with material. The nobbled on bones do not show
cracking or other weathering effects, so they 
apparently were covered up not long after.

He mentioned another find of a pathological nature. He
showed a slide of an adult's "pubic club" (his words) 
with a hole clean through it. Other parts of the skeleton
show the infection spread through the body. He figures it
took a few months for the adult to die - and it died at
the nursery. Those bones are not nibbled on.

As to what caused the hole, he speculates a stegosaur
of some kind.


END EXTRACT.

rich