Fraud, Altruism & Medicine in Nature
by Jack Kittredge
I like learning about how animals act. Sometimes they are so similar to humans that I feel we’re not so far ahead of them as we think. Three examples I recently read about particularly got me musing on this.
The first is a grisly case of what security officials might call a sleeper-cell. A study published February in the Annals of the New York Academy of Sciences looks at gossamer-winged butterflies in the family Lacaenidae. Their larval stage they spend as caterpillars that can trick their way into an ant colony and get the worker ants to care for them until they become butterflies and fly away. If not tended, the caterpillars will eat the ants’ young.
The way these insect parasites gain entry is by hacking the nest password, in this case by using acoustic and chemical communication to mimic the ants’ own behavior. Evolutionary biologists have suggested this represents “an evolutionary arms race in communication” with the ants constantly trying to detect the invaders and keep them out and the caterpillars producing sounds and vibrations that more and more copy those of the defenders.
Other examples of such misrepresentation among animals include cuckoos and cowbirds laying eggs in a host’s nest and the hatchlings, to be fed, then mimicking the foster species’ calls, the margay cat which duplicates the distress cry of baby tamarin monkeys to lure their parents into range, and loons raising mallard chicks which cleverly imitated the host parents’ behavior.
On a more cheerful note, the incredible drone-captured video footage released last week in Science of eleven sperm whales clustering to lift a baby whale up out of the water to take its first breath cannot but warm even a Grinch’s heart. Whales have been reported to help each other out (usually when closely related) so, say social biologists, they are helping preserve ‘family’ genes. But this recent case involved unrelated individuals and looks like simple benevolence.
Unselfish behavior has been noted among vampire bats and also chimpanzees sharing meals, social insects serving the queen, and vervet monkeys sounding alarms even when doing so endangers them. Of course any animal highly devoted to others will likely fall behind in the race for genetic success, so it is hard to imagine altruism winning any Darwinian race, just occasionally showing up for a quick dash.
The Indonesian Orangutan (whose complex sex life is attracting more and more study from fans) has been observed performing long-term and purposeful activities using a medicinal plant to heal a major wound. Such a flanged (don’t ask) 35-year old Sumatran great ape ‘Rakus’ was injured badly in a fight and emerged with a part of his face torn or bitten off. Fortunately, he was being observed by scientists for other reasons (they should blush) who filed a detailed report on his actions for the next several days in the journal Scientific Reports.
Rakus sought out the plant akar kuning or yellow root, which is known among Southeastern Asians as having inflammatory reducing and anti-bacterial properties, (which stem from an alkaloid called berberine). It is not normally eaten by orangutans, but Rakus ingested some and actively chewed a larger quantity which he then applied to his wound. He kept this healing process up for several days, at the end of which the wound was barely visible and had no sign of infection.
Such self-medication is not unknown among animals, although Rakus exhibited unusual planning and constancy to effect his remarkable improvement. Chimpanzees in Gabon have been known to chew flying insects and apply them to their wounds. Orangutans in Borneo have been reported to chew up plants with anti-inflammatory and analgesic properties and then rub them on their arms and legs, presumably to soothe muscles. Many animals are known to eat bitter plants to expel worms and parasites. Various birds are known to rub themselves in ants which will go after feather mites and other parasites.
Is any of this so far from our behavior? A small percent of us do seem willing and able to make a living from others using careful observation, guile, misrepresentation and clever mimicry. The vast majority of us look out for ourselves but occasionally someone runs into a burning building to save a neighbor’s child. We all find relief from normal aches, pains, and wounds using products derived from plants, animals, insects, soil or fungi.
I guess my point is we don’t seem that different from animals – I think we live more along a continuum with other life rather than having dominion over it. As we find out more about the natural world I expect we will be impressed at how well it functions and how much we have to gain from a little respectful study.
