Photo of Dr Thomas Price

Dr Thomas Price

Senior Lecturer Evolution, Ecology & Behaviour

    Research

    Meiotic drive

    Me, catching flies in Tunisia
    Me, catching flies in Tunisia

    I am trying to understand the population dynamics of the selfish X chromosome SRS in the European fruit fly Drosophila subobscura. In Tunisian populations about 20% of flies carry a driving X chromosome called SRS. Normal X chromosomes are passed on to half a male’s offspring, while the other halfinherits his Y chromosome. But when males carry the SRS chromosome all their Y bearing sperm die and all their offspring inherit the SRS X chromosome. This allows the SRS chromosome to spread as it is passed on to more offspring that the normal X, but it also causes male carriers to only have daughters, and to produce less sperm than normal males. This can cause populations to mostly consist of females, and potentially could wipe entire populations out due to a total lack of males. Work in related species has shown that if females mate with multiple males the small amounts of sperm produced by carrier males is usually swamped by the large amounts of sperm transferred by normal males, and the driving X cannot spread. But in D. subobscura, SRS is only found in the Southern populations where females remate, and is never found in the Northern populations where females mate once. It’s a bit of a mystery.

    I am trying to understand the molecular and genetic basis of the drive mechanism in this species, and releted ones. Ultimately, if we can understand sex chromosome drive, we might be able to use it to control pest species, or to modify the sex ratio of important agricultural animals. But our understanding of how these mechanisms work, how they evolve, and how they persist, is still at a very early stage.

    Mating behaviour and fertility

    Drosophila mating
    Drosophila mating

    Some female animals mate once in their life while others mate with many males each day. This results in big differences between species in everything from their physiology and behaviour, to how their social systems are arranged. A male fathers fewer offspring if a female he mates with goes on to mate with another male. This has caused the evolution of male traits that reduce female remating rates. The establishment of harems in red deer and gorillas are well known examples. Male honeybees genitalia burst inside the female in an effort to block her reproductive tract and prevent her mating with other males. Females in turn have often evolved traits that allow them to avoid control by males, and remate with males of their choosing.Finding the genes underlying female remating would be a big step forward in understanding all this variation, and I am searching for these genes using the fruit fly Drosophila pseudoosbcura.

    I am also interested in how environmental and genetic differences, including meiotic drive (see above), can impact on fertility, particularly male fertility. We know that sperm is hard to produce at high temperatures, which is why many mammals have external testes that keep their sperm cool, and birds also have sperm cooling mechanisms. But how will ectotherms cope if they are exposed to increasing temperatures as climate change progresses? I am trying to find out, using a variety of fruit fly species.

    Sexual cannibalism

    I work with mantids as well as flies when studying cannibalism
    I work with mantids as well as flies when studying cannibalism

    Praying mantises, various spiders, and quite a lot of other animals, famously indulge in sexual cannibalism- females eating the males they mate with. I am trying to understand why some species, populations, and individuals are more likely to behave this way. And what are the implications for the survival of populations? Can populations go extinct because all the males get eaten? I investigate this in a variety of praying mantis species and spiders.

    Research Grants

    The genetic basis of reproductive isolation through intragenomic conflict

    NATURAL ENVIRONMENT RESEARCH COUNCIL (NERC)

    April 2019 - April 2022

    When to be choosy? The evolution of mate choice in animals

    LEVERHULME TRUST (UK)

    September 2018 - September 2022

    Meiotic Drive Frequency in Morrocan Drosophila

    EUROPEAN SOCIETY FOR EVOLUTIONARY BIOLOGY (SWITZERLAND)

    March 2015 - August 2016

    Will fertility loss at high temperatures determine species responses to climate change?

    NATURAL ENVIRONMENT RESEARCH COUNCIL (NERC)

    March 2017 - March 2020

    Why females mate once: from genes to populations

    NATURAL ENVIRONMENT RESEARCH COUNCIL (NERC)

    March 2011 - August 2014

    Polyandry and sex ratio drive

    NATURAL ENVIRONMENT RESEARCH COUNCIL (NERC)

    February 2012 - November 2015

    Is any male a threat or is fitness a factor?

    ASSOCIATION FOR THE STUDY OF ANIMAL BEHAVIOUR (UK)

    June 2012 - August 2012

    Comparative genomics and gene expression profile of sexual and parthenogenetic Ischnura hastata (Insecta, Odonata) - ODOGEN

    EUROPEAN COMMISSION

    May 2014 - April 2016

    Winter is coming: sperm competition during hibernation

    THE GENETICS SOCIETY (UK)

    July 2013 - August 2013

    Research Collaborations

    Gregory Holwell

    Project: Sexual cannibalism
    External: University of Auckland

    We try to understand the evolution and consequences of cannibalism.

    David Hosken

    External: University of Exeter

    Mike Ritchie

    External: The University of St Andrews

    Rhonda Snook

    External: University of Stockholm

    We work on how climate change will affect fertility

    Amanda Bretman

    External: The University of Leeds

    We work on understanding how climate change will impact on fertility

    Nina Wedell

    External: University of Exeter