4.1.2 Genus level
Environmental variables play a significant role in shaping the abundance
and distribution of prey species, influencing the availability of
suitable habitat for sea snakes. Studies on Aipysurus indicate
that environmental factors play crucial roles in shaping their
distribution and abundance. (Lynch et al. 2023) reported that
environmental factors are important in shaping the behavior and
distribution of A. laevis , while (Borczyk et al. 2021) found
sexual dimorphism in skull size and shape for A. eydouxii , which
may affect feeding and ecological niche differentiation between males
and females.
Previous studies have also highlighted the importance of environmental
variables in the distribution and population dynamics ofEmydocephalus . (Lukoschek et al. 2007) found that E.
annulatus exhibited metapopulation dynamics influenced by prey
abundance, habitat quality, and complex reef habitats, while (Goiran and
Shine 2013) reported a decline in E. annulatus abundance on a
protected coral reef system in the New Caledonian Lagoon, attributed to
changes in the physical environment resulting from anthropogenic
modification to the system. Our study found that Sal, Sil, and Tem are
significant variables for both PC and PI at different resolutions,
consistent with (Brischoux et al. 2012) finding that oceanic salinity
influences body condition. However, we found a discrepancy in our
results regarding the importance of Tem compared to a previous study onE. annulatus , which reported no significant effects of annual
thermal variation on population densities. Further research is necessary
to clarify these discrepancies and enhance our understanding of the
importance of environmental variables, such as salinity and other
nutrient variables, in the distribution and population dynamics ofEmydocephalus .
For Ephalophis , our findings align with the idea of a rapid
radiation of sea snakes, driven by adaptations to environmental factors.
The importance of adaptation to the marine environment is highlighted by
the variable importance of environmental factors observed inEphalophis . This is supported by previous studies on sea snakes
in Australian waters (Sanders et al. 2013), molecular phylogeny of sea
snakes (Lukoschek and Keogh 2006), association between habitat type and
skin thickness in snakes (Shine et al. 2019), presence of paddle-shaped
tails in viviparous sea snakes (Sanders et al. 2012), and the feeding
strategies and foraging ecology of the Hydrophiinae sea snakes, as
analyzed in previous studies (Hampton 2019).
The Hydrophis genus is found to have almost identical results to
the whole lineage analyzed, indicating a similar influence of
environmental variables on their distribution and abundance. Meanwhile,
discussing the Laticauda genus alone may be redundant as it
represents the whole Laticaudinae subfamily. Further diverse ecological
research is needed to support the findings and test the relative
importance of variables for the Microcephalophis genus. Overall,
the importance of environmental factors in shaping the ecology and
evolution of sea snakes is reinforced by the results obtained from our
analysis. We also emphasize the importance of further diverse ecological
research to support the findings and test the relative importance of
variables for this genus.