The Dinosaur Lens

Were dinosaurs really as terrible as we believe?

Ask an average person for a word to describe dinosaurs and you’re likely to hear terms like ‘savage’, ‘vicious’ or ‘deadly’. But this is very unlikely to be an accurate description of life in the Mesozoic era – the Age of Reptiles. Certainly, there were animals alive at this time who seem to us to be terrifying monsters – both in terms of their size, and their natural weaponry. Yet if dinosaurs were really as horrific as we tend to imagine them then either their descendents, the birds, would have to be equally savage and deadly, or an unprecedentedly rapid change of behaviour must have occurred.

The problem occurs in large part because of the decidedly narrow window on the past available to us. The fossil record contains some wonderfully preserved specimens of creatures past, and often offers considerable forensic data about their demise. But this creates a distorting lens effect in our appreciation for dinosaur life by skewing our knowledge heavily towards the deaths of these animals and away from their lives. It may be the case that what we can be most confident about in terms of our knowledge of these creatures relates to their deaths (or at least those whose remains survived), but any plausible account of their lives must allow more than this.

The possible complaint that to go beyond the evidence is to indulge in pure speculation is hollow when television ‘documentaries’ concerning the lives of dinosaurs almost constantly engage in imaginative fiction (often presented as if it were empirically based). The rise of CGI animation has allowed for some terrifically entertaining shows featuring dinosaurs – but the oft-used phrase “scientists believe” is merely a way of papering over speculation, and many shows don’t even bother to admit this aspect of the presentation. Since our beliefs about dinosaurs have changed wildly over the last century – and continue to change with both fresh finds and new studies of previous fossils – the suggestion that any of these alleged documentaries presents a factual face of dinosaur life is absurd. Rather, the most dramatic stories are chosen because these shows are at their heart entertainment.

If we approach the representation of the dinosaurs from a different stance we will reach different conclusions. The common lineage of dinosaurs with the birds around today was originally conceived in the 1960s, a source of controversy in the 1970s, and a point of orthodoxy by the 1990s. Although behaviour can change in animals over very short time scales, this is largely because animal behaviour is not genetically determined but rather a confluence of response to environment, learning, and natural tendencies (which are, in part, affected by genetics). It is extremely likely that the behaviour of dinosaurs lies within a landscape of possibilities bounded by reptiles on one side and birds on the other – and we would be hard pressed to find the savagery of popular dinosaur mythology supported in that space. Even the crocodiles and alligators, which are literally dinosaurs that survived the end of the Cretaceous, are not quite as vicious as their popular image suggests.

If we consider the text book figure of dino-terror, the Tyrannosaurus Rex, palaeontologists are still not agreed as to whether this was an apex predator, like a lion, or a scavenger, like a hyaena. It is quite likely that real tyrannosaurs engaged in both active predation and scavenging of kills, which only muddies the waters, but either way, feeding was only a part of tyrannosaur life. These animals had to have bred, which means they have to have mated – their lives must have involved more than killing. The shadow sides of their lives are occasionally covered by dinosaur media – T-Rex: Back to the Cretaceous represents a tyrannosaur mother caring for her offspring, for instance – but it is generally downplayed in favour of their more dramatic role as a murderous monster.

What’s more, even accepting tyrannosaurs preyed upon hadrosaurs and cerotopsians doesn’t justify treating them as more vicious or savage than big cats that prey on grazing animals today. In many respects, the relationships between herbivorous dinosaurs and their carnivorous predators seems highly likely to parallel contemporary relationships between herbivorous mammals and their predators. Thus what we observe of the lion’s hunt of the zebra or the wolf pack’s hunt of a deer may well be behavioural prototypes of cretaceous hunts by tyrannosaurs and (say) velociraptors  respectively. Yet ask someone on the street which is more vicious or savage, a lion or a Tyrannosaurus Rex, and they are far more likely to choose the latter – without any empirical justification.

Predatory dinosaurs feel like monsters to us for much the same reason sharks do – a disturbing collection of teeth, a diet of meat and a worrying excess of scale that allows us to imagine ourselves as ill-fated prey. Yet in both cases, the lives of these animals were or are more rich and varied than a focus on hunting and feeding suggests. The portrayal of these animals in the popular media – both in documentaries and elsewhere – distorts our understanding of their lives with a lens effect that is every bit as slanted as our view of the world when seen through the eyes of our news services. We are often aware of this lens effect, but we are never immune to it.