10.5061/DRYAD.GXD2547J8
Shine, Richard
0000-0001-7529-5657
Macquarie University
Brown, Gregory
0000-0002-2924-9040
Macquarie University
Kosmala, Georgia
University of Sydney
Skin morphology in cane toads
Dryad
dataset
2020
CAPES*
BEX/13734-13-0
Australian Research Council
https://ror.org/05mmh0f86
FL120100074
Coordenação de Aperfeicoamento de Pessoal de Nível Superior
https://ror.org/00x0ma614
BEX/13734-13-0
2020-08-18T00:00:00Z
2020-08-18T00:00:00Z
en
16679 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
The structure of the skin may evolve rapidly during a biological invasion,
for two reasons. First, novel abiotic challenges such as hydric conditions
may modify selection on traits (such as skin thickness) that determine
rates of evaporative water loss. Second, invaders might benefit from
enhanced rates of dispersal, with locomotion possibly facilitated by
thinner (and hence more flexible) skin. We quantified thickness of layers
of the skin in cane toads (Rhinella marina) from the native range
(Brazil), a stepping-stone population (Hawai’i), and the invaded range in
Australia. Overall, the skin is thinner in cane toads in Australia than in
the native range, consistent with selection on mobility. However, layers
that regulate water exchange (epidermal stratum corneum and dermal Ground
Substance layer) are thicker in Australia, retarding water loss in hot dry
conditions. Within Australia, epidermal thickness increased as the toads
colonised more arid regions, but then decreased in the arid Kimberley
region. That curvilinearity might reflect spatial sorting, whereby mobile
(thin-skinned) individuals dominate the invasion front; or the toads’
restriction to moist sites in this arid landscape may reduce the
importance of water-conservation. Further work is needed to clarify the
roles of adaptation versus phenotypic plasticity in generating the strong
geographic variation in skin structure among populations of cane toads.
Histological examination