Brazilian toads turned out to be almost invulnerable to scorpion venom – during the hunt they can withstand dozens of bites of these arachnids. An increase in the number of these toads will reduce the scorpion population and reduce the number of people who suffer from them. A study by scientists from the Butantan Institute is published in the journal Toxicon.
The yellow scorpion of the species Tityus serrulatus is considered one of the most dangerous in Brazil – and every year both the size of its population and its bites are growing. Scientists believe that these arachnids have spread to all areas of Brazil and neighboring countries due to the fact that their females can give birth without mating.
Another reason for the constant increase in the number of Tityus serrulatus is the lack of predators – toads must eat them, but scientists still do not know for sure whether they eat scorpions and what is the resistance of amphibians to poison.
In a new study, scientists followed the toads of the species Rhinella icterica: in particular, they studied the reaction of amphibians to scorpions, and then introduced different doses of poison to them. Half of the toads received a lethal dose for mice (that is, poison from two scorpion bites), and the remaining five times as much poison.
The experiment showed that toads perceive scorpions as prey and try to catch them. However, scorpion bites – even if there were more than 10 – did not have any poisonous effect on them.
Researchers note that in order to reduce the scorpion population in Brazil, it is necessary to maintain and increase the number of toads. Now their natural habitat is being disturbed as a result of tree felling.