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Homoroselaps lacteus (Linnaeus, 1758) is a species of polymorphic, ornately-coloured lamprophiid snakes from southern Africa. Herpetologists have long recognised that the three colour morphs are largely geographically predictable, with barred individuals occurring in the south-western Cape, blotched individuals occurring in the Eastern Cape Province, and striped individuals occurring across the north eastern parts of the geographic distribution. Several workers have speculated that the colour patterns represent different species--an idea corroborated by a recent publication that showed significant genetic divergence between a small number of samples. Here we draw on meristic data from the examination of 148 specimens, geo-referenced digital images of 131 animals, phylogenetic maximum likelihood analysis of molecular sequence data (16S, cyt-b, RAG-1) from 23 individuals, and species distribution modelling approaches to examine the evidence for species-level differentiation within the group. Additionally, we present a thorough summary of the diet of H. lacteus as revealed by examination of museum specimen gut contents and observations drawn from a social media platform used to gather dietary data for southern African herpetofauna. Our results reveal that, in general, the three colour morphs occupy three parapatric geographical ranges which correspond broadly with three well resolved phylogenetic clades. However, not all specimens could be unambiguously assigned to one of the three colour patterns or phylogenetic clades suggesting additional evolutionary complexity within the clade. Our meristic data revealed a subtle increase in the number of ventral scales and subcaudal scales of the barred colour morph relative to the two other forms, however our dietary data suggested that diet is largely conserved across the clade, being restricted to the consumption of elongate squamate reptiles. We conclude by discussing the implications of our findings for the systematics of H. lacteus, and highlight the value of integration of morphological, molecular, and ecological data in understanding the evolutionary origins of snakes. [ABSTRACT FROM AUTHOR]

The secretive nature of snakes makes their behaviour and activity patterns difficult to study in a natural setting. This is especially true for alert, actively foraging snakes such as Cape Cobras, whose vigilance while foraging can easily result in significant observer effects. Additionally, Cape Cobras may spend a major portion of each day underground, making traditional focal animal analysis an extremely inefficient method for collecting information on their activity. Over recent years, biologging has become more important in the study of free-ranging animals. Custom built bio-logging devices attached to, or implanted into, large highly mobile and active mammals have proved to be very successful in collecting data on a range of physiological and behavioural traits. However, this has been less successful for small, less active animals such as snakes. We used implanted iButtons to record body temperature (Tb) of telemetered free-ranging Cape Cobras in the Kalahari Desert, South Africa. We inferred the behaviour (e.g., inactive underground; active above ground; basking etc.) of snakes from the resulting Tb profiles. We then compared our inferences of Tb profiles to field observations in a ground truthing exercise to verify the accuracy of our interpretations. Tb profiles revealed distinctive patterns that, when compared to environmental temperatures (Te), allowed us to score behaviour remotely. This made it possible to assess activity periods in relation to time of day, season and Te. We concluded from the thermal profiles that if active, the cobras display a daily bimodal activity pattern in summer, and occasionally forage at night. During the hot months of the year, the snakes spend a large proportion of their active time foraging and less time basking. The snakes usually limit surface activity to the mornings and evenings as they avoid the hottest hours of the day. In the winter months, however, the snakes may come out more frequently and regularly but if active they stay on the surface during the warmest hours in the middle of the day. While foraging behaviour occurs less in winter the snakes bask frequently close to their shelter and tend to stay on the surface for longer periods than in summer. This method opens the path to assess and analyse the thermal ecology of free-ranging animals without human disturbance. [ABSTRACT FROM AUTHOR]

Conventional approaches to studying snake diets rely upon visual identification of prey items obtained either via palpation of meals from live snakes, examination of faecal remains, or from gut contents of preserved specimens. These approaches can be biased, invasive, and often do not depict the full dietary breadth of a species. Molecular approaches provide novel mechanisms for gathering information that allows us to increase our knowledge and understanding of a predator's prey intake. Here, we propose a project that demonstrates the use of molecular analysis of snake faeces to study the diet of Psammophis crucifer and Psammophylax rhombeatus. We intend to use PCR analysis in conjunction with DNA cloning techniques to identify prey items of known identity from faecal samples of captive snakes thereby testing the hypothesis that molecular techniques can be used to identify, to species level, the remains of prey items in the faeces of these two species of snakes. Should our approach be successful, researchers would be able to sample snake diets at the population level with high intensity, including resampling individual snakes, all in a relatively non-invasive manner. [ABSTRACT FROM AUTHOR]

An incomplete understanding of the feeding ecology of organisms impedes our ability to address questions related to energy flow within an ecosystem, predatorprey dynamics, population dynamics, niche partitioning, habitat preference, and the evolution of behaviours and traits. For most African snake species, it is difficult to study feeding ecology due to low detectability of study organisms and an even lower incidence of in situ feeding observations. Moreover, the cost and time associated with extensive field sampling are often prohibitive and sampling often involves destructive methods. In our study, we harnessed the power of Facebook as a crowdsourcing platform, which is comprised of thousands of potential observers, to collect photographic records of predation events involving reptiles and amphibians in sub-Saharan Africa. Feeding events in snakes were particularly well-represented with nearly 1,000 feeding events recorded in the last four years. To evaluate the usefulness of this method, we compared the observations collected from Facebook to observations we recorded from an extensive literature review on the diets of wild southern African snakes (~3,200 feeding observations). An analysis of the two datasets revealed how effectively and rapidly information on these difficult to detect ecological interactions can be collected at broad spatial, temporal, and taxonomic scales. Our work highlights that our understanding of snake feeding ecology is far from complete and that multiple methods should be utilised to compile a comprehensive and robust dataset. [ABSTRACT FROM AUTHOR]