The family Sphecidae It includes hundreds of species of insects known as “digging wasps”, although it is no Vespe and being more related to bees. Beyond these taxonomic misunderstandings, the digging wasps are exceptional animals, equipped with an out of the ordinary memory: the confirmation comes from a study published on Current Biology which shows how the Vespe Madri organize the distribution of food to their larvae according to a complex program and which involves keeping a large amount of information in memory.
The wasps and caterpillars. The “wasps” observed for the study belong to the species Adminand live in Surrey’s hacksaws. Lay their eggs in the sand, digging small holes in which transport a caterpillar and deposit the egg on it: in this way, when the larva emerges has the food necessary to grow. After that, they cover the nest with the sand.
The digging wasps there then return a few days later – From 2 to 7, depending on the size of the caterpillar: the bigger it is, the more time it passes between one visit and the other. They discover the hole, control that the larva is still aliveand if it is other food; after they close the hole againand this time forever – or at least until the larva is mature and ready to emerge.
Iron memory. The team that studied the digger wasps observed almost 1,300 visits to the nests, which, it is worth reiterating it, are dug in the sand and surrounded by hundreds of other holes made by other wasps. Despite this, they manage to remember the position of nine different nestsand they are practically never wrong: of these 1,300 visits, only 1.5% was a mistake (that is, a mother nourishes someone else’s larva).
The experiment on the digging wasps has also put them to the test in other ways: for example, exchanging food in the nests, putting bigger caterpillars where the mother had put some of them and vice versa. The result is that the wasps have adapted, making more time pass between the two visits where the larvae had more food available.
