Invading clonal
wasps. Chestnut menace spreading
yet no males required.
The Chestnut gall wasp arrived in Europe in 2006, imported accidentally from China. Since then it has begun to spread and devastate European Chestnut trees.
Bonal et al (2018) have now revealed that the European population has very low genetic diversity due to 1) the founding of the population by a small number of individuals, 2) an endosymbiont bacterial infection present within the population that is known to have male-killing tendencies and 3) it’s parthenogenetic reproduction strategy. This is where females are able to reproduce and produce female offspring without the need to be fertilised by males. No males have been observed in the European population and the females and their offspring are effectively clones of one another.
Original research: https://doi.org/10.1038/s41598-018-23754-z