Promiscuous mating in the endangered Australian lizard Tiliqua adelaidensis: a potential windfall for its conservation

Abstract

13Studies have revealed an unsuspected complexity in social systems within a few lizard 14 species, including group living, long-term monogamy and individual recognition of partners 15 or offspring. Comparisons among these species and their relatives could provide valuable 16 insights, allowing us to investigate traits that are shared across social systems and identify 17 general principles relating to the evolution of sociality. The endangered pygmy bluetongue 18 lizard, Tiliqua adelaidensis, is a member species in the Egernia group, but is thought to show 19 a more solitary social structure than other members in this group. Within this study we used 20 microsatellite markers to determine the mating system of T. adelaidensis. Unlike many other 21 species in the Egernia group, we found a predominately promiscuous mating system in T. and the ability to recolonize newly available habitat and avoid inbreeding (Greenwood 1980). 45Many species have evolved social mechanisms and mating systems in large, continuous 46 habitats, but now occupy isolated fragments of habitat, with consequential impacts on their 47 dispersal and mating systems (Stow et al. 2001, Levy et al. 2010. Knowledge of the mating 48 system and how it has changed with restricted dispersal is an important component in the 49 sustained management of these species. 50How have different mating systems and levels of sociality evolved among related species? where they ambush passing invertebrate prey (Hutchinson et al. 1994, Milne et al. 2003. However, the secretive lifestyle of this species makes it difficult to observe whether there are 104 any social associations among neighbouring lizards, or whether the mating system is 105 polygamous as may be predicted if this is a more asocial species. We used genetic analysis to 106 identify the parents of juvenile pygmy bluetongue lizards in populations from two locations, 107and to determine the mating system used by this species. We had two aims. The first was to (Table 6). That is, there was no evidence that partners were chosen non-297 randomly from among neighbouring lizards with respect to relatedness. 298Further evidence that relatives were not discriminated against as mating partners, came from 299 three offspring resulting from matings between partners with relatedness values of 0.500, 300 0.365 and 0.297 (Table 5). In each case other less related individuals were available as 301 partners from among neighbouring lizards ( In our study, males were recorded as far as 100 m away from the females they mated with. 332Records of mating have all been in the spring (October) (Milne et al. 2003, Fenner and Bull 333 2009). This is the time when other observations have suggested that males of this normally 334 sedentary lizard are actively moving around (and exposed to predation). It is the time of year 335 when a male lizard was found inside a brown snake stomach in 1992 when the species was 336 re-discovered (Armstrong and Reid 1992), and also the time of year when Schofield et al. 337(...

Parasite in peril? A new species of mite in the genus Ophiomegistus Banks (Parasitiformes: Paramegistidae) on an endangered host, the pygmy bluetongue lizard Tiliqua adelaidensis (Peters) (Squamata: Scincidae)

“…Mating, which is promiscuous within seasons (Schofield et al . ), would be the main instance of contact between T. adelaidensis adults. Ectoparasite transmission during mating has been proposed as likely in Hemidactylus mabouia geckoes with Geckobia mites (Rivera et al .…”

“…Mating in T. adelaidensis is promiscuous within and between seasons, and mate choice appears to be influenced only by spatial proximity (Schofield et al . ). Aspects of the lizard's unique biology such as reliance on burrows, its low level of conspecific interaction and its low vagility are likely to heavily influence the mite's lifecycle, transmission ecology and genetic structure.…”

The impact of sheep grazing on burrows for pygmy bluetongue lizards and on burrow digging spiders

“…Of specific relevance to ectothermic arthropods and lizards, grazing can alter microhabitats, and the ranges of associated available microclimates and thermal opportunities (Vitt et al, 1998), potentially leading to decreases in their population densities (Woodcock et al, 2005). Moderate grazing may also benefit some species if a reduced cover of vegetation provides better opportunities for behavioural thermoregulation, foraging and detecting poten-tial predators (Pettigrew & Bull, 2012;Schofield et al, 2012Schofield et al, , 2014Ebrahimi & Bull, 2015). Thus, the impact of grazing on a particular habitat can be complex, potentially benefiting some species while disadvantaging others.…”

Pre-processing Techniques to Improve the Efficiency of Video Identification for the Pygmy Bluetongue Lizard

“…They are found exclusively in remnant fragments of native grassland in South Australia's mid-north (Li et al, 2009), (Tohl et al, 2013), (Staugas et al, 2013), (Schofield et al, 2013). Identification of individual lizards is essential for ecological studies.…”