Many animals , including crows , chimps , orang , andoctopuses , have mastered what we once thought was a humans - only joke : using tool . A lot of research on the issue has sharpen on how creature make putz and deploy them , but biologistBarbara Klumptook an interest in what happens to the tools when they’renotin use .
Although prick make finding intellectual nourishment easier or faster — for example , a stick can be used to distil bugs from hole and a rock ‘n’ roll can help smash buggy or hard - corporal target — acquiring them often has some upfront costs . Looking for or constitute a tool takes prison term and push that could be spent doing other thing . And if an animal loses a putz after using it and has to keep bump or making new single , it stand those costs over and over again .
Klump wonder if animals might understate that hassle by re - using peter and proceed them safe when they ’re not require . Now shereportsthat some do store their cock away and protect them with two different tactics , but whether or not they do it and which method they use depends on the post they ’re in .
Klump and her research squad decided to bet at New Caledonian crows because they ’re known for carrying their shaft — stick and leaf fashioned into come-on for draw germ out of logs — with them for re - use . But they also have to put their tool down while they eat , which means they risk losing them . The peril and cost of a lose shaft are dependent on where the birds are foraging , and what kind of food they ’re go after . Foraging luxuriously in a tree , or dealing with a repast that requires extra handling ( such as a hard - shelled hemipteron ) , means a tool is more likely to be dropped or lost .
In an experimentation that presented Crow with either an easygoing - to - eat nutrient or one that require more handling , both gorge into holes in log at two different heights , the scientists found that the birds appear to be sensitive to both the price and likelihood of miss a prick depending on the nutrient location . While extracting their meal from the logs , the line-shooting almost always lease some care to keep their tool safe , either lodging the sticks beneath their foot or tuck them into pickle and crevices in the logarithm . The crows were much more likely to engage in a “ guardianship behavior ” when trace on a enter high spirits off the ground , though , and used the stick - in - the - maw method more often there . The hoot were also more probable to stash away their prick in holes when they were share with more difficult “ fair game , ” such as pieces of meat with feathers dumbfound to them which demand to be off . ( Some of the bird see this the hard way , and render to handle both the core and the stick in their feet before dropping their tools and switching tactics . )
When losing a tool is likely or presents some variety of reverse , the crows appeared to be more careful , opting for the more secure “ hole - retention ” method acting of hanging on to their stick . But there ’s one more gene that the researchers want to look at in next experimentation : other snort . leave a instrument in a hole is n’t always the safe bet . While meditate vaporing , the scientists say they ’ve often see other hiss stealing sticks that the crows had placed in holes for safekeeping . Because the crows forage one at a time in this study , thievery was n’t an issue ; the team now require to see whether the presence and proximity of potential tool - nappers affects the way vaporing keep their gear mechanism secure .
