In
1982, Dale Russell, then curator of vertebrate fossils at the National
Museum of Canada in Ottawa, conjectured a possible evolutionary path
that might have been taken by Troodon had it not perished in the
K/T extinction event 65 million years ago, suggesting that it could have
evolved into intelligent beings similar in body plan to humans. Over
geologic time, Russell noted that there had been a steady increase in
the EQ (the relative brain weight when compared to other species with
the same body weight) among the dinosaurs. Russell had discovered the
first Troodontid skull, and noted that, while its EQ was low compared to
humans, it was six times higher than that of other dinosaurs. If the
trend in Troodon evolution had continued to the present, its
brain case could by now measure 1,100 cm; comparable to that of a human.
Troodontids had semi-manipulative fingers, able to grasp and hold
objects to a certain degree, and binocular vision. Russell proposed that
this "Dinosauroid", like most dinosaurs of the troodontid family, would
have had large eyes and three fingers on each hand, one of which would
have been partially opposed. As with most modern reptiles (and birds),
he conceived of its genitalia as internal. Russell speculated that it
would have required a navel, as a placenta aids the development of a
large brain case. However, it would not have possessed mammary glands,
and would have fed its young, as birds do, on regurgitated food. He
speculated that its language would have sounded somewhat like a bird
song. Russell's thought experiment has been met with criticism from
other paleontologists since the 1980s, many of whom point out that
Russell's Dinosauroid is overly anthropomorphic. Gregory S. Paul and
Thomas R. Holtz, Jr., consider it "suspiciously human" and Darren Naish
has argued that a large-brained, highly intelligent troodontid would
retain a more standard theropod body plan, with a horizontal posture and
long tail, and would probably manipulate objects with the snout and
feet in the manner of a bird, rather than with human-like "hands".
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