Climate change, phenotypic plasticity and ageing: a case study in a long-lived bird
Project description
In
response to climate warming and earlier springs, many animals have been
reported to start reproducing earlier in the season, with cascading
effects on growth trajectory and final size. It raises however many
unanswered questions on the mechanisms accounting for those phenotypic
changes and their long-term consequences.
Several
non-exclusive processes can explain phenotypic changes at the
population level in response to climate change. For example, if
individuals
that reproduce earlier in the season are recruiting more offspring in
the population, and if the start of reproduction is heritable, gene
copies coding for early reproduction will increase in frequency within
the population. This mechanism is best known as
microevolution. Moreover, individuals may also adjust their
reproductive timing to the prevailing environmental conditions, by
either advancing or postponing their reproduction in warm or cooler
years, which is referred to as phenotypic plasticity. The role
of phenotypic plasticity in driving population responses to climate
and, most importantly, whether this process is heritable and can respond
to selection, remains to be investigated in details. Furthermore,
although it is well accepted that changes in growth
trajectories can have long-lasting effects, contrasting predictions can
be made depending on the genetic and environmental contributions
driving those changes. On one hand, theories of ageing hypothesised the
existence of genes with antagonistic pleiotropic
effects on growth, reproduction and the rate of ageing. It predicts
that genes favouring fast growth are also favouring high reproductive
investment early in life and a fast rate of ageing. On the other hand,
the silver spoon hypothesis points out that individuals
born under favourable conditions will enjoy a fast growth, high
reproduction and a slow rate of ageing. Yet, the long-term effects of
climate change on growth rate, reproduction and ageing, and their
underlying mechanisms, remain elusive.
Because
long-lived species are likely to encounter a wide range of
environmental conditions during their reproductive lifetime, they are
expected
to be under strong selection for displaying adaptive phenotypic
plasticity. Long-lived species are thus excellent study systems to
address the contribution of gene and/by environment effect on
reproductive timing, growth trajectories and the rate of ageing.
The
aim of this PhD project is to investigate the links between climate
change, phenotypic plasticity, and ageing in the long-lived Alpine swift
(median lifespan is 7 years). This species shows strong inter-annual
variation in reproductive timing and growth trajectories. Furthermore,
breeders are highly faithful to their colonies, which offers the
opportunity to analyse changes in reproductive timing
and offspring growth from the same parents across years with
contrasting climatic conditions. For this project, you will be using
both archived data from a long-term (>20 years) dataset as well as
collecting new data in the field. This project will offer opportunity
to learn a variety of important methods in ecology and evolutionary
biology and to participate in the field work. The student will be given a
thorough training in field skills and in statistical analyses to
identify climatic variables and their consequences
on traits, model growth and plasticity, and to tease apart the amount
of trait variance explained by genetic and environmental effects.
Relevant publications
Kroeger S, Armitage KB, Reid J, Blumstein DT,
Martin, JG.A. 2020. Older mothers produce more successful daughters. Proceedings of the National Academy of Sciences of the United States of America
Martin JGA
et al. 2017. Genetic basis of between- and within-individual variance
of docility. Journal of Evolutionary Biology, 30(4):796-805.
Martin JGA, Festa-Bianchet M. 2011.
Age-independent and age-dependent decreases in reproduction of females.
Ecology Letters 14: 576-581.
Bize P, Daniel G. Viblanc VA,
Martin JGA, Doligez B. 2017. Negative phenotypic and genetic
correlation between natal dispersal propensity and nest-defence
behaviour in a wild bird.
Biology Letters 1
Bize P et al. 2010. Sudden weather deterioration but not brood size affects baseline corticosterone levels in nestling Alpine swifts.
Hormones and Behavior 58: 591-598
Bize P et al. 2003. Parasitism and developmental plasticity in Alpine swift nestlings.
Journal of Animal Ecology 72: 633-639
Supervisory team
The project will be supervised by
Pr. Julien Martin (uOttawa) and Pierre Bize
(University of Aberdeen, Scotland). The student will be based at the
Biology department of the University of Ottawa. He/she will have the
opportunity to perform field work over the summer in Switzerland
and to visit the co-supervisor lab in Scotland.
Ottawa
consistently ranks among the best Canadian cities. You’ll love an
easy-going lifestyle that appeals to urban adventurers and nature lovers
alike. Enjoy a revitalized city that is bursting with energy. Gigs,
festivals, theatre and art are all close by in a walkable downtown core.
And, having the 2nd highest concentration of scientists and engineers in North America, you’ll have lots
of opportunities to build up your network and kick-start your career.
Financial support
Financial support is available for 4 years. The student is expected to complete two teaching assistantship per year.
Candidate Profile
For this PhD project our ideal candidate:
-
has a MSc in biology
-
is creative, highly motivated and can work alone or in teams
-
has strong interest in evolutionary biology and quantitative genetics
-
has strong interest for statistical analyses and past experience with R programming
How to apply
Students
that are interested should send a writing sample (thesis, paper or
scientific article), a CV, a motivation letter, and the contact of two
references to Pr. Martin (julien.martin@uottawa.ca)
and Dr Bize (pierre.bize@abdn.ac.uk). We will start interviewing candidates in early July and continue to consider applications until the position is filled.
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Dr. Julien Martin
Biology department University of Ottawa
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Dr.Pierre Bize
Department of Biological Sciences University of Aberdeen
pierre.bize@abdn.ac.uk
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