Current project: Automatic Acoustic Observatories – non-invasive long term monitoring of acoustic species
Advice to aspiring scientists: “I made the [initial] mistake of wanting to do everything by myself when working with other people who are just as interested in your area can be wonderful.”
Selected publications: Mayhew, P.J., Jenkins, G.B. & Benton, T.G., (2008) A long term association between global temperature and biodiversity origination and extinction in the fossil record.
It is not rare for researchers to find themselves face to face with challenging questions about the natural world that cannot be answered in a single paper. Rather than attempting to understand phenomena independently, individuals from different areas of expertise focus their efforts on collectively tackling such questions as units of a larger body: the scientific community. The compiling of findings across different subfields allows scientists to build on each other’s knowledge and take steps in the right direction towards concrete answers. With aims of further understanding how the diversity of life came to be, Dr Peter Mayhew’s choice to research insects due to their species richness and high diversity between lineages is a great example of how a specialist’s perspective can be applied to address a much broader scientific question.
Particularly interested in but not limited to studying parasitic wasps within the Hymenopteran order of insects, Dr Mayhew’s work has taken multiple approaches towards understanding the evolution and global distribution of parasitoid species and what it could mean for other insect groups and evolution as a whole. After a short talk with Dr Mayhew, his genuine passion was made apparent through his explanations and descriptions of journeys his research has taken him on. Such dedication may be the very reason he has been able to successfully apply insect models to evolutionary ecological study as well as study on the global distributions of parasitic wasps.
Hymenopteran insects carry out different jobs based on their sex, for this reason, all species within the group have specialised sex determination mechanisms allowing mothers to choose the sexes of their offspring. Parasitic wasps, for example, have haplodiploidy, the ability to birth males from unfertilised eggs and females from eggs fertilised by male gametes. The larval stage of these wasps earns them their title as parasitoids. Once eggs are laid within host insects by queen wasps, larvae burrow their way out upon hatching; feeding on their host until sufficiently developed. Queen parasitic wasps have the remarkable ability to select the gender of the implanted egg by fertilising it using stored male gametes to create females or leaving it unfertilised to create males. Female offspring regularly require more nutrition as future mothers, thus are commonly implanted within larger hosts than male eggs.
Rather than observing births of all females from large hosts and births of all males from smaller hosts, some male larvae are observed in large hosts and vice versa. From an evolutionary perspective, this overlap prevents offspring from developing in their optimal environments potentially leaving some female larvae underfed. Dr Mayhew hypothesised the limitations of the queen’s own nervous system could explain why sex ratios are not optimal. Using a computer-based neural network designed to mimic the shortcomings of an organism’s nervous system, similar sex ratio’s as those observed in nature were seen; supporting an evolutionary ecological hypothesis which suggests complete optimisation of sex ratios can be limited by the parent’s own abilities.
Apart from his studies of evolutionary ecological phenomena Dr Mayhew’s work has brought him as far as Brazil’s Serra dos Órgãos national park to study the geographical distribution parasitic wasps and other species in habitats as high as 2200m above sea level. The park is home to rare forest biomes known as Atlantic Rainforests where specimens were collected at various sea levels to determine whether different species inhabit different altitudes. If so, this would make an argument for conserving the park’s higher altitude habitats currently threatened by ever-rising tree lines due to climate change. Having collected many potentially unknown species of insects as part of a research group, the specimens stored in Brazil could take as long as 20 years to sort through. Dr Mayhew’s ability to conduct a wide range of projects around a central topic demonstrates devotion to his calling. He recognises the insight his specialist work could provide in answering much broader questions about life’s diversity and species conservation.
The amateur watercolour painter and astronomy hobbyist feels research can be balanced with other aspects of life and emphasises the importance of finding interests outside your field.