Centipedes have incorporated the weapons of bacteria and fungi into their venoms, experts suggest.
As part of an ongoing, wider study into centipede venoms, researchers set out to discover whether centipede venom toxins may have evolved elsewhere in the tree of life, in places other than their direct, arthropod ancestors.
Venom expert Dr Ronald Jenner, from the Natural History Museum, together with his colleague Dr Eivind Undheim found that the creepy crawlies have repeatedly stocked their venoms with proteins that independently evolved within bacteria and fungi.
The centipedes have acquired these toxin components through a process known as horizontal gene transfer.
Horizontal gene transfer is a process by which genetic material moves between distantly related organisms – in this case between bacteria and fungi, and centipedes.
It is distinguished from the movement of genetic material from parents to offspring and from ancestors to direct descendants – known as vertical gene transfer.
Dr Jenner said: “This discovery is remarkable. It reveals the largest, most diversely sourced contribution of horizontal gene transfer to the evolution of animal venom composition known to date.”
Many studies have been carried out into the venoms of animals like snakes, scorpions, spiders, often because they are dangerous to humans.
However, as centipedes are not dangerous to humans, their venoms have not had too much focus.
But interest is rising and the processes happening within centipede venom evolution show it is fertile ground for investigating phenomena such as horizontal gene transfer.
Dr Jenner said that “three of the five venom protein families that centipedes have acquired by horizontal gene transfer are used by bacteria explicitly to exploit their hosts”, including by damaging their cells by the formation of pores.
While the mechanisms behind horizontal gene transfer, especially from bacteria to animals, are not well understood, it is known to have contributed a range of adaptive benefits to different groups of animals.
The paper is published in Nature Communications.