Poisons are an efficient defence mechanism for many organisms. The downside is that the production of poisons can be quite expensive. The manufacture of poisons can use up a lot of resources that could be used for other purposes, depending on the substances being made. Because of this, some animals must rely on their diet to acquire poisons. Imagine the monarch butterfly.
Because it Uses it For Protection, The African Crested Rat is Dependent on Which of The Following?
Caterpillars ingest milkweed and store the plant’s toxins in their bodies, making the adult butterfly toxic to predators. Examples like this exist among invertebrates, but recently, researchers have confirmed that at least one mammal has evolved a similar technique.
Acquaint yourself with the African crested rat (Lophiomys imhausi). Its gargantuan proportions and brightly patterned fur give the impression that a skunk and a porcupine had an explosive sexual affair. However, it is composed entirely of rats, and it has a remarkable defence plan that begins with the poison arrow tree, a species of tree found in many places of eastern Africa (Acokanthera schimperi).
Plant’s Sap as a Poisonous Coating
Native Americans have been using the plant’s sap as a poisonous coating for arrows for centuries, earning the toxin it generates the name ouabane (also spelled “arrow poison”). Humans aren’t the only mammals to benefit from this sap. It’s also used by the African crested rat.
Along its back, the African crested rat develops a crest of highly specialised hairs. When the rat feels threatened, it raises its porous, thick hairs into a crest and displays its characteristic black and white colours.
It was hypothesised that the poisonous crest of hairs on the rat was responsible for the collapse into convulsions and death experienced by predators like dogs that attempted to devour the rat. This was only proven recently.
Scientists Researching these Rats have Picked Up on Some Peculiar Social Dynamics.
They found that many of the rats in their study routinely ingested poison arrow tree twigs and branches by chewing and licking them. The plant poisons are transferred to the specialised hairs by this behaviour.
Due to their large surface area, individual hairs are capable of absorbing a great deal of the harmful chemicals. The rats, surprisingly, don’t seem to be affected by the sap’s toxicity. Potentially, their sodium pumps in their heart muscles have been genetically altered to resist the poison.
They may be able to digest the toxins because of a particularly diverse microbiome in their gut. The rats’ conduct does not appear to be poisonous to them.
To our knowledge, this is the first mammal to store up plant toxins for later use in a defensive strategy. It’s incredible to imagine that a rat may adopt a defence mechanism originally developed by a plant to ward off predators. It is thought that the special bond between rats and trees is deteriorating.