VENOMOUS THEROPODS

[darren.naish@port.ac.uk]

It's taken all day to go through the email backlog - this 
follows my wedding-related absence during which I went through Battle 
(home of _Becklespinax_) and saw the UK's only captive _Squatina_. 
What a cool fish. Wedding parties are cool too, I must do one again 
some time. Meanwhile, theoretical statistics should be banned from 
the list. 

Graeme kindly answered my questions re: source of the 
assertion that _Neovenator_ had a poisonous bite. Graeme writes..

"I merely reported information from the paper describing the animal 
(at least, I think that was where it came from - I don't have a copy 
handy to check, but I'm sure someone will quickly correct me if I'm 
wrong) that bacteria left in the animal's mouth from rotting meat may 
have served to infect bites made in prey and perhaps contribute to 
the later demise of said prey."

There is no mention whatsoever of such speculation in the 
_Neovenator_ paper (Hutt et al. 1996). The authors of the paper 
(Hutt, Martill and Barker) were, I am afraid, not at all pleased on 
finding that such a speculation had been made. It is without 
foundation. However, I am still very curious as to the source. 
Suggestions that _Tyrannosaurus_ may have been an infector-killer are 
well known, and are based on (probably erroneous) comparisons with 
_Varanus_. Crichton's musings about the widespread presence of 
venomous bites in theropod dinosaurs have had a marked effect on 
layperson perception of inferred predatory behaviour in theropods 
and, I think, in other macropredators as well. Recently, veteran 
zoologist Clinton Keeling reported his bemusement on being questioned 
about the supposed presence of a venomous bite in _Panthera leo_ 
(Keeling 1997). Keeling concluded that this belief was based on a 
reading of Livingstone's experience with a lion (which occurred in 
southern Africa some time late in the last century) in which, 
though his arm was broken in several places and he was badly mauled, 
Livingstone experienced a kind of painless numbness. Incidentally, 
the lion that attacked Livingstone may have been one of the very last 
Cape lions left in the wild (Naish 1997). My suspicion - I wrote this 
up for the magazine _Mainly About Animals_ but never bothered to 
submit it - is that people are assuming the presence of poisonous 
bites in a wide variety of macropredators, following the implication
of Crichton that they are widespread. Which they are not. Bakker has 
plugged into the Crichton bandwagon: he wrote in _Earth_ magazine 
('Bakker's field guide to the dinosaurs of Jurassic Park') that 
poisonous theropods were 'likely', given that many kinds of tetrapod
have evolved a poisonous bite. 

But outside of 'Jurassic Park' (and associated fiction), I am not 
aware of any suggestions, other than Graeme's in _Dinoworld_ that any 
theropods other than tyrannosaurids had poisonous or venomous bites. 

"Patterns in nature are what demand explanation"

DARREN NAISH
darren.naish@port.ac.uk