Global Assessment of Reptile Distributions
  • Home
  • About
  • People
  • Activities
  • Meetings
  • Publications
  • Data
  • Links
  • Collaborations
  • BloGARD

Island life only works if you’re easy-going – uncovering predictions of the island syndrome for lizard clutch size variation

18/9/2017

1 Comment

 
In a recent publication in the Journal of Biogeography we show that Insular lizards with variable clutch sizes follow the predictions of the island syndrome, while lizards with fixed clutches do not.
Life-histories of insular species are hypothesized to slow down, a phenomenon known as the "island syndrome". Insular individuals are thus expected to lay smaller clutches of larger eggs compared with individuals belonging to closely related mainland species. Most lizards have variable clutch sizes and can lay any number between one egg and a species-specific maximum, which can be well over 50 eggs. Many lizards, such as geckos and anoles, however, lay invariant small clutches of one or two eggs, and may thus be unable to manifest some aspects of the island syndrome. We tested whether insular species with either variable or invariant clutch sizes respond to insularity differently by analyzing egg, clutch, hatchling and female sizes and brood frequencies of 2,511 lizard species.
Picture
Mediodactylus kotschyi (photo Rachel Schwarz)
Picture
Pafilis & Rachel, Kalogria region NW Peloponnes (photo Shai Meiri)
We found that insular species with variable clutch sizes lay smaller clutches of larger eggs, from which larger hatchlings emerge, compared with mainland species, as expected by the island syndrome. Lizards with invariant clutch sizes, however, lay smaller clutches on islands and increase clutch frequency, compared with mainland species, perhaps because of limitations set by the female body cavity and pelvic opening. This may result from lower seasonality of tropical islands, leading to a greater spread of reproductive effort, or as a result from fluctuations in population densities caused by tropical storms. Our results also emphasize the importance of taking differences in life-history traits into account while studying lizard reproductive traits on large phylogenetic scales.
Picture
Kampana islet (photo: Rachel Schwarz)
Author: Rachel Schwarz
1 Comment

    Author

    Mainly maintained by Shai Meiri and Uri Roll

    Archives

    October 2022
    May 2022
    November 2021
    June 2020
    March 2020
    February 2020
    January 2020
    July 2019
    January 2019
    October 2018
    August 2018
    May 2018
    November 2017
    October 2017
    September 2017
    January 2017
    August 2016
    July 2016
    May 2016

    Categories

    All
    Africa
    Amniotes
    Australia
    Big Data
    Big-data
    Body Size
    Body-size
    Climate
    Clutch Size
    Clutch-size
    Competition
    Conservation
    Deserts & Drylands
    Diet
    Diversification
    Diversity Patterns
    Ecogeographic Rules
    Euroasia
    Evolution
    Extinctions
    Functional Diversity
    GARD History
    Geckos
    Hotspots
    In Memoriam
    Islands
    Island Syndrome
    Late Quaternary
    Latitudinal Diversity Gradient
    Lizards
    Longevity
    Metabolism
    New Guinea
    Nocturnality
    Palearctic
    Priritization
    Reproduction
    Speciation
    Tetrapods
    Tropics
    Type Specimens
    Viviparity
    Wikipedia

    RSS Feed

Powered by Create your own unique website with customizable templates.