It’s a motion more closely associated with horses, but researchers have found that more species of crocodiles can gallop than previously thought.
The study, led by the Royal Veterinary College in Britain, also found that, by contrast, alligators and caiman, also members of the Crocodylian family, cannot manage more than a trot.
Despite the difference in gaits, crocodiles and alligators can all move at about the same speed – no more than 11 miles per hour.
The ability to gallop — and to use an even more extreme gait called a bound — is likely down to the size and build of the Crocodylia in question.
For their study, researchers at the college set up video cameras at the St Augustine Alligator Farm and Zoological Park in Florida. Working alongside experts from that organisation, they studied the gaits and speed of 42 individuals from 15 species of Crocodylia.
They found that, as expected, larger Crocodylia moved relatively more slowly, with athletic ability decreasing as size increases.
However, while many popular and scientific accounts previously assumed only a few species of crocodiles could gallop and bound, the researchers discovered that a further five species can in fact do so, including the critically endangered Philippine crocodile.
This now means at least eight species in total can gallop and bound.
“We were really surprised at one major thing: despite the different gaits crocodiles and alligators use, they all can run about as fast,” said Professor John Hutchinson, a specialist in evolutionary biomechanics at the college who was study lead.
“So why do some crocodiles choose to gallop? We suspect that bounding and galloping give small crocodiles better acceleration and manoeuvrability, especially useful for escaping from danger. It seems like alligators and caiman stand their ground rather than run away with an extreme gait.”
John Brueggen, Director of St Augustine Alligator Farm and Zoological Park, said: “We have been witnessing these behaviours in many of our specimens over the years, but it was wonderful to finally formalise these observations in a scientific study.”
The study findings are published in Scientific Reports.
This study was funded in part by a grant to Hutchinson from the European Research Council.