Re: JFC-Bloodiest Battle ??

[Erik Boehm <erikboehm07@yahoo.com>]

> Given the lack of similarity between theropods and living
> terrestrial vertebrates, 
This statement of course excludes Birds.
We can definitively state we know of a therepod that is a primary scavenger-> a 
vulture, but this isn't applicable to allosaurs for obvious reasons.

> It would not surprise me that they are making
> livings in ways unlike anything around now, including a life based
> primarily on scavenging.  As Peter Dodson once wrote "let dinosaurs
> be dinosaurs."

As far as scavengers go, I can't think of many scavengers today. Aside from 
vultures, scavenging seems to be a secondary behavior. Hyena's are well known 
for scavenging, but hunt as well (vulture hunting being very rare). 
Hyena + Vulture scavenging typically relys on a larger predator(or in a 
vultures case, a car+roadkil) to kill the prey first. If Allosaurus wasn't 
taking down the saurpods, what was? if nothing was, what was it scavenging? or 
did it go for smaller prey.

Large animals typically have much lower mortality rates, I doubt an allosaurus 
(unless it could become facultatively cold blooded to lower energy 
requirements)could sit around and wait for sauropods to get sick/old/injured 
and die before eating them, it must have had another food source.

Do you presume it primarily scavenged smaller animals and bullied smaller 
predators away from their kills - like a pack of hyenas often will "steal 
kills"(substituting size for numbers)?

Seagulls will "scavenge" a lot, particularly around humans, but also hunt 
rather well.(once again, this scavenging presumes a food source - is there any 
evidence sauropod 

Hyenas, Seagulls, etc seem to be generalist feeders. Allosaurus doesn't scream 
"generalist" at me.

Of course Dinosaurs got way bigger than anything on land today, and many things 
don't scale well(arthropods for example), so it isn't right to just take a role 
today, and apply it to an animal much larger. A 6 foot bumblebee like 
pollenator would be ridiculous for example.

Likewise, caveman hunters running Mammoths off a clif to their death couldn't 
scale down to work with extremely small species (generically: "bugs"), as the 
fall wouldn't kill them(or they would be able to scale the cliff like many 
lizards and squirrels/rodents). 

Increased size and weight may open up new niches (while closing others), 
particularly for predation. An animal could be so big it could barely stand 
under its own weight, allowing for a much less agile predator, or a reduction 
in its ability to defend itself (there has to be a point where increasing size 
stops decreasing vulerability to a given predator)


Size doesn't change everything, but it does change a lot.


Given some sauropods rivaled whales in size, it might be worth looking at 
whales as a food source.
I know of no obligate whale scavenger... there are interesting video's on 
youtube of a bunch of great whites eating a whale carcass- devouring it real 
fast, but it is well known their primary food source is from predation of much 
smaller animals.

As to regular whale predation, (Megaladon aside), the only examples I know of 
involve a few killer whales going for juvenile whales.

I have to ask, does anyone know the relative size ratio of an Adult grey whale 
vs a typical sauropod of its time, and the ratio of an Orca vs a typical Adult 
Grey whale?

If we look at much smaller terrestrial non-volant vertebrates we don't see 
primary scavengers.

If we look at the only other ecosystem with animals of similar sizes, we don't 
see primary scavengers OR hunters of full grown adults (except in rare cases).

Hunting juvenile sauropods seems the most likely to me.

Neither living example correlates well due to scale limitations, or the big 
difference between terrestrial and aquatic predator/prey niches.