Article
Diversity in Morphology and Locomotory Behavior Is Associated with Niche Expansion in the Semi-aquatic Bugs
Registro en:
CRUMIÈRE, Antonin J. J. et al. Diversity in Morphology and Locomotory Behavior Is Associated with Niche Expansion in the Semi-aquatic Bugs. Cuurent Biology, v.26, p.3336-3342, Dec. 2016.
0960-9822
1879-0445
Autor
Crumière, Antonin J. J.
Santos, M. Emilia
Sémon, Marie
Armisén, David
Moreira, Felipe F. F.
Khila, Abderrahman
Resumen
Acquisition of new ecological opportunities is a major
driver of adaptation and species diversification
[1–4]. However, how groups of organisms expand
their habitat range is often unclear [3]. We study
the Gerromorpha, a monophyletic group of heteropteran
insects that occupy a large variety of water
surface-associated niches, from small puddles
to open oceans [5, 6]. Due to constraints related
to fluid dynamics [7–9] and exposure to predation
[5, 10], we hypothesize that selection will favor
high speed of locomotion in the Gerromorpha that
occupy water-air interface niches relative to the
ancestral terrestrial life style. Through biomechanical
assays and phylogenetic reconstruction, we
show that only species that occupy water surface
niches can generate high maximum speeds. Basally
branching lineages with ancestral mode of locomotion,
consisting of tripod gait, achieved increased
speed on the water through increasing midleg
length, stroke amplitude, and stroke frequency.
Derived lineages evolved rowing as a novel mode
of locomotion through simultaneous sculling motion
almost exclusively of the midlegs. We demonstrate
that this change in locomotory behavior significantly
reduced the requirement for high stroke frequency
and energy expenditure. Furthermore, we show
how the evolution of rowing, by reducing stroke frequency,
may have eliminated the constraint on body
size, which may explain the evolution of larger Gerromorpha.
This correlation between the diversity
in locomotion behaviors and niche specialization
suggests that changes in morphology and behavior
may facilitate the invasion and diversification in
novel environments. 2030-01-01