In 2010 , scientists set off exploring the Abanda cave organisation in Gabon after getting a tip about something foreign living there : crocodiles . And not just any crocodiles . Orangecrocodiles .
Crocodiles will sometimes practice cave as temporary recourse during droughts , but the dwarf crocodile ( Osteolaemus tetraspis ) in the Abanda caves seemed to have involve up permanent abode there . When wewroteabout the sashay a few years ago , the research worker did n’t know much about the cave crocs . They cognise they were there , they knew they were uncanny , and they knew some of them had turned orange . The scientists , take by biologistMatthew Shirley , have since gone back into the cave to study the animals . Their newpaper , issue inAfrican Journal of Ecology , overturns some of their early ideas about the Abanda crocodile , showing that life in the cave has been just to them , and offer a new explanation for their unusual colors .
After seeing the crocodile for themselves , the squad began survey the cave and capturing crocodiles by bridge player , taking their measurements and determining their gender . To see what the reptiles were exhaust , they used a method called the hose - Heimlich proficiency , which is precisely what it sounds like . While one scientist flushed a croc ’s belly with an improvised belly pump , another grab the fauna and squeezed its belly , rout out the water and the stomach contents through the animal ’s mouth . They did the same with a group of crocodiles hold out aboveground at streams in the timberland around the caves .
While the forest crocs barfed up fresh water crabs , shrimp , crayfish , and a form of insects , the cave crocodiles were eating cave cricket and bat — and little else . The divergence in dieting , the research worker say , indicate that cave crocodile do n’t hunt down or feed aboveground and belike have very small contact with their neighbour . The animals have to hail out of the cave to breed and lay their eggs because there are n’t any suitable places to build nests in there , but they apparently do n’t spend much time on the control surface . They ’re not entirely immobilise in the caves , as the researcher once thought , but they ’re still very isolated .
Abanda Expedition
Even with all that fourth dimension spent in the cave , the Abanda crocs do n’t appear to be changing in reply to life underground . Despite some strong-arm and genetic differences between them and the forest crocs , the researcherssaythat the cave crocodiles “ showed no signs of physical adaptation , or repercussion , of living in a hypogean environment”—such as the reduced pigmentation or smaller eyes often encounter inothercave - dwelling animals . The only notable strong-arm change the team thinks is link to their modus vivendi is the crocs ’ orange skin . They ab initio thought that the gloss change might have been an adaption to living in duskiness or have by their dieting . But they now have a different — and gross — idea .
With thousands of bats hanging from the cave roof , the floor has become covered in a acerbic variety of H2O and bat waste . “ We hypothesize that the orangish coloration in large adult is cause by ‘ bleaching ’ of the skin after what is presumably years of inundation in bat guano , ” the investigator say . In some cases , they incur , the guano is n’t just bleaching the crocs ’ skin and change its color , but wear away it to the stop where the scientists could distinctly see the animals ’ skull peeking out through the hide .
Those do n’t vocalise like the best living conditions , but the caves offer up plenteousness to make up for it . After take up all the animals ’ measurements , the researchers find that the cave crocodiles were in good strong-arm condition than any of the crocs living aboveground . The squad think this is because the cave crocs ’ prey — cricket bat and crickets — is abundant ( keep down in the tens of thousands ) , easy to catch , and available year - round . Furthermore , the caves allow a stable microclimate and aegis from the elements . The researchers also found more crocodile in the caves than they did in the ring timberland , where the animals are vulnerable to logging and bushmeat hunt , lead them to think that the caves also provide some safety from humans . survive in guano may have its price , but at the close of the day , it ’s not easy being immature .
