Solitary Hunters and T. rex

["Constable,Miles [Edm]" <ConstableM@mail.edm.ab.doe.ca>]

Here's my 2 cents worth. There are a few solitary hunters that routinely 
take large prey, sometimes larger than themselves, the ones that come to 
mind are: the lynx (in Europe at least), weasels (taking rabbits), stoats 
(taking rabbits in Europe), Bengal and Siberian Tigers, black and grizzly 
bears (taking elk and moose in N. Am.), and cougars (taking sheep and deer 
in N.Am.). As far as I recall most predators are quite capable of bringing 
down adults of their prey species, otherwise they would starve eventually. 
While they will not turn down an easy-to-kill juvenile, they will not spurn 
an adult if the conditions are right. With solitary hunters there typically 
are a lot of kill attempts, with only a few actually being successful. So, 
what does this say about T. rex? Darned if I know. But I suspect that a 
hungry adult T. rex would consider anything a meal until proven otherwise 
either by it escaping or standing it's ground. However, the prey items of 
solitary hunters do not typically stand their ground, they run for it. So 
the danger to the hunter is not that great. Now the question of whether 
Ceratopseans would run or fight is important. It might depend on whether 
they were spooked and ran or saw the T. rex coming and had time to get 
around to meet it. Of course more than one T. rex would make this a moot 
point for a single Ceratopsian, it was dead meat. I think the 
Ceratopseans/Hadrosaurs/whatever else, would run as a herd and hope they 
weren't the one to feel T. rex's bite.

As for a model of maternal upbringing there are plenty of different 
mammalian strategies around, I suspect that T. rex might have used a more 
"lizard-like" strategy, for example how alligators "raise" their young. They 
incubate the eggs, guard the nest and assist the young into the water and 
may even hang around where the young are for some time protecting them from 
some obvious predators, including male alligators. Then they are on their 
own, predating small animals like tadpoles, insects, etc. Gradually their 
prey items get larger as they do and they either co-exist with others in the 
bayou, get eaten or move out. A considerable number of young alligators get 
eaten by all sorts of predators, so the population is controlled through 
high infant mortality, emmigration and starvation. This sounds to me like a 
more workable hypothesis for T. rex maternal behaviour than one based on 
mammals (who are smarter than your average lizard). Young and adult 
alligators do not cooperate in hunting as a rule, but they are likely to try 
for the same prey item. Young T. rex's would simply hunt smaller animals 
like mammals, young of other species, eggs, insects?, whatever was in their 
size range to subdue. Or, perhaps they followed ma around with her 
sufferance and snarfed scraps from her kills, or perhaps she fed them for a 
while and scared off hungry males. More information on the ecosystem they 
operated in would be of great use, as the strategies usually conform to what 
and how much is available for the young to eat. It is something we are not 
going to learn about until we find a T. rex skeleton with babies or eggs, or 
someone invents a time machine.

As an aside, I suspect we would call a group of young T. rex's a "murder". 
As in "a murder of crows", but for a much better reason.

Miles Constable
One time biologist and Interested paleontological spectator.