In “Nile crocodile is two species” (Nature, September 14, 2011), Ed Yong reports,
he iconic Nile crocodile actually comprises two different species — and they are only distantly related. The large east African Nile crocodile (Crocodylus niloticus) is in fact more closely related to four species of Caribbean crocodile than to its small west African neighbour, which has been named Crocodylus suchus.
Genes from both living crocodiles and mummies were sequenced.
Apparently, the ancient Egyptians knew that suchus was different. It was docile enough to use in religious ceremonies.
The name C. suchus was coined in 1807 by the French naturalist Geoffroy Saint-Hilaire, who singled it out as a subspecies of Nile crocodile. However, his ideas were not widely accepted. “He called it the sacred crocodile in one of his papers,” says Hekkala. “We’ve talked about proposing that as a common name.”
Saint-Hilaire probably knew about the Egyptian preference. We are told that the bigger, fiercer species, Niloticus, “could have” ridden currents around the Cape of Good Hope and eventually into the Caribbean, because slave traders used these routes and “especially since crocodiles can store sperm and go without eating for up to 10 months.” And when they get tired, they can just go down the hold and catch a nap.
Maybe we haven’t heard the last of this story.
Nile croc attacks buffalo herd at water hole:
See also: Crocodiles swam to North America?