100 Influential Papers - page 10

Harper, J.L. (1967)
A Darwinian approach
to plant ecology.
Journal of Ecology,
55, 247-270.
Harper synthesised the fundamental
principles defining a discipline
and drafted the path for later research. He recalled our
‘distinguished parenthood’, shared with population geneticists,
and he advocated Darwin’s quantitative approaches to ask why
demographic thinking hadn’t yet permeated plant ecologists’
agendas. Nature is made up by numbers and, more specifically,
by the balance among them. Harper argued that numbers can
be difficult to translate directly into the real essence of plant
populations. But he used the pioneering studies of Tamm, Sagar,
and Antonovics on declining plant populations to advocate the
value of plant numbers. Tallying numbers is needed to estimate
the balance between added and disappeared individuals in a
way that can be translated into genetic selection studies or
estimates of ecosystem fluxes. When coupled with studies of
plant vigour, numbers are invaluable in assessing processes of
population regulation. Harper showed how the allocation patterns
of vegetative/reproductive structures subtly influence density-
dependence by determining population turnover rates, and he
provided a range of predictions about life-history patterns. He
built a convincing case for experimental approaches to the study
of plant coexistence under field conditions. Harper doubted his
ability to deal adequately with the part played by plant-animal
interactions, but I think he had the ability (see web site account).
Pedro Jordano
S ECT I ON ONE
POPU L AT I ON DYNAM I C S
07
Murton, R.K., Isaacson, A.J. & Westwood, N.J.
(1966)
The relationships between wood-pigeons and their
clover food supply and the mechanism of population
control.
Journal of Applied Ecology, 3, 55-96.
Employed by the Ministry of Agriculture, Fisheries and Food
to study woodpigeons as pests, Murton and his team carried
out an extensive study. Whilst this could easily have just
been a useful piece of research, their thoughtful approach to
population ecology and behaviour resulted in a study with
pioneering methods and concepts. By simultaneously studying
the clover food supply and the bird’s behaviour and ecology they
determined the functional response, the aggregative response
between food density and woodpigeon distribution, the impact
of food on annual abundance and within flock variation in
intake. Other components of this remarkably complete study
included examining the dynamics of clover within pigeon-
proof exclosures, determining the response to severe weather,
measuring body condition and assessing the long term response
of the clover population to grazing. Combining these elements
leads to their theory as to how the population is regulated: most
birds are in good condition but when the population is high
relative to the food supply the few birds in worst positions gain
insufficient food, lose mass and either die or leave. By integrating
behaviour with ecology, theory with fieldwork, observations with
experiments, condition with demography, and local distributions
with interannual changes, the paper set the stage for the study
of vertebrate responses to their food supply and for answering a
range of applied questions.
William J Sutherland
08
Perrins, C.M. (1965)
Population fluctuations and clutch-size in the great tit,
Parus major
L.
Journal of Animal Ecology, 34, 601-647.
The long-term study of great tits,
Parus major
, at WythamWood, near Oxford, has contributed a great deal to our
understanding of population dynamics, and this paper by Perrins which formed the foundation for much of the
work that followed, is still widely cited nearly 50 years after its publication. It was written at a time when
there was much debate about how natural selection operated; whether on the individual or on the
group. Perrins provided clear evidence that great tits did not limit their reproductive effort for
the good of the species. Instead, individual birds maximised their lifetime reproductive
success according to the resources available to them, and population size
was limited by food supply rather than the birds themselves. It has since
become one of the classic examples used in teaching to explain the fallacy
of ‘good of the species’ arguments and group selection in general.
Ian Hartley
10
1
09
JL Harper
1,2,3,4,5,6,7,8,9 11,12,13,14,15,16,17,18,19,20,...48