Last night's Horizon was promising: what might have happened if the asteroid that is generally agreed to have triggered the extinction event at the end of the cretaceous period 65 million years ago had missed? This should be good, I thought. Interesting to speculate about how dinosaurs might have continued to evolve. What forms might they have evolved into by now..?
But the programme was spoiled by an unnecessary and scientifically dubious focus on the question "what would have happened if humans had co-evolved along with dinosaurs?".
Given the extraordinary success of the dinosaurs in exploiting ecological niches (as the programme pointed out) the likelihood that mammals would have evolved very much beyond the rodent-like animals (like Repenomamus) that managed to just about co-exist with dinosaurs must be vanishingly small. (Clutching at straws perhaps) the programme suggested that the tree-tops might have provided a dinosaur-free niche in which primates might have evolved, but failed to address the question of why dinosaurs would not have also moved into the same eco-space, especially with fresh mammalian meat to tempt them.
But for me the programme makers lost it completely with the suggestion that intelligent humanoid dinosaurs might have co-evolved with humans. Now I love thought experiments, but the idea that homo dinosauroid would now be peacefully sharing our 21st C. cafe culture is, frankly, insulting to dinosaurs. We were shown a rather meek and frightened looking specimen (well you would be too with no clothes on) - clearly 21st C. homo d. needs to get down to the gym.
Now I have no problem at all with the idea that dinosaur evolution, if it had not been rudely interrupted by the Chicxulub asteroid, might have resulted in highly intelligent dinosaurs, language, culture and so on (especially given emerging evidence for gregarious behaviour in dinosaur groups). If the asteroid had missed, and (against the odds) primates and hominids had evolved alongside intelligent dinosaurs, the suggestion that the two lineages would have somehow co-evolved into a peaceful vision of Dinotopia is, well, just unbelievable*. Much more likely is that the dinosaurs would have been subject to another and equally lethal extinction event. Man.
*I say this with the greatest respect for the wonderful books of James Gurney.