Sanjaya Weerakkody

University of Colombo · Department of Zoology

In recent years, policy-driven conservation has frequently been faulted for their lack of biological foundation. Evidence-based conservation provides an alternative way to take decisions on prioritizing areas for conservation based on the available biological diversity within the given areas. The study was carried to identify to conservation value...

Altitudinal gradients offer an ideal research setting to investigate the patterns of distribution of parasites, vectors, hosts, and host immune responses across different environmental conditions. However, very few studies had been done on the parasite profile in birds along the altitudinal gradient in Asia. The study was conducted at the Issengard...

Yellow wagtail complex was long considered a single species (Motacilla flava). Recent phylogenetic studies however, split this species into two; the Western Yellow Wagtail (Motacilla flava) and the Eastern Yellow Wagtail (Motacilla tschutschensis). Until 2020, there were no records of the Eastern Yellow Wagtail in Sri Lanka. Nonetheless, using seve...

Hybridization or introgression enables species to mix traits, allowing horizontal gene flow and varying parental alleles and phenotypes. Belihuloya, located in the intermediate zone is a transitioning point between dry and wet zones, where two sister species, the Sri Lanka Drongo (Dicrurus lophorinus), limited to the wet zone, and the Greater Racke...

Hybridization or introgression enables species to mix traits, allowing horizontal gene flow and varying parental alleles and phenotypes. Belihuloya, located in the intermediate zone is a transitioning point between dry and wet zones, where two sister species, the Sri Lanka Drongo (Dicrurus lophorinus), limited to the wet zone, and the Greater Racke...

Parasites thrive by consuming host resources, causing a decline in host fitness. This burden drives host evolution, exerting selective pressure on both. The main objective of the study was to investigate parasitic profile and host immune responses in avian hosts along altitudinal gradients in Sri Lanka. This research took place in the Issengard Bio...

The model of allopatric speciation in an island biogeographic framework suggests that the division of ancestral mainland populations lead to two or more allopatric island species through natural or sexual selection, or through genetic drift. Climatic conditions can influence the process of speciation by creating physical barriers that prevent gene...

The Kentish Plover Charadrius alexandrinus Linnaeus 1758 is a common shorebird in Eurasia and North Africa that breeds in a variety of habitats, exhibits different extents of migratory behaviour, and is an emerging model species of breeding system evolution. Here we focus on the resident population found across the southern tip of India and Sri Lan...

We reviewed the systematics of Lycodon striatus (Shaw, 1802), including all available name‐bearing types of its synonyms after evaluating phylogeographic (genetics), morphological (morphometry, meristic, and hemipenes), osteological and distribution evidence. Lycodon striatus sensu lato is widely distributed throughout South and Central Asia and mi...

Nesting within the arthropod nests is rare but can be found in several lineages of birds. In Asia, only the Rufous Woodpecker (Micropternus brachyurus) (RUWP) shows this peculiar nesting behavior where it breeds inside the nest of the Crematogaster ant. This study focused on the symbiotic relationship between RUWP in Sri Lanka (M. b. jerdonii) and...

The variation in climatic conditions over space and time is considered a major driving force in speciation. Gloger's rule is one such rule that broadly explains the variation in the colouration of endotherms (birds and mammals) with the effects of climatic parameters. This predicts that endothermic animals tend to have darker colouration in warm an...

Based on phylogenetic and morphological characters, we revise the systematics of the natricid genus Fowlea in Sri Lanka, comprising two morphospecies. The taxonomy of the Sri Lankan populations has long been controversial, and one of the species has, for more than a decade, been listed as Xenochrophis cf. piscator. Although the Sri Lankan populatio...

Many passerines possess extravagant vocalizations which often provide evolutionary advantages. Birds have evolved many variations in vocalization in order to withstand the associated costs. The current study focused on investigating intraspecific vocal variations in Sri Lanka Bush Warbler (Elaphrornis palliseri) which is a range restricted montane...

In 2006, the western purple-faced langur (Semnopithecus vetulus nestor) was listed as among the world's 25 most endangered primates. A field survey conducted the following year indicated that its population was threatened by human activities , especially deforestation. To address this threat, meetings were held with the community leaders of Waga, a...

Sexual dimorphism driven by exaggerated phenotypes is widespread among birds. Besides their evolutionary function, there are many associating costs. Hence some species of birds have evolved optimized signaling mechanisms enabling them to overcome the cost of conspicuousness. Iris dichromatism plays a key role in making one sex is distinguishable fr...

Ratufa is giant arboreal squirrels restricted into South and South East Asia. They are diverged into four phenotypically different taxa; Ratufa macroura, R.indica, R.bicolor and R.affinis. Sri Lanka’s Grizzled Giant squirrel; R.macroura is the most range-restricted species of the genus being endemic to Southernmost India and Sri Lanka. The phylogen...

The typical model of allopatric speciation in island biogeographic framework suggests that the division of ancestral mainland populations leads to two or more allopatric island species through natural or sexual selection or through genetic drift. Here we studied the phylogenetic status and phenotypic variation of Dicrurus paradiseus allospecies com...

Sri Lanka's geological history, varied cllmate and topography have shaped its rich speciesdiversity (Abeyrama &Seneviratne, 2017: Weerakoon et al., 2012). lts climate is driven mainly by the monsoonal rains and topography; where there is a south-central mountainous region, which rises to an elevation of 2, 500 m, surrounded by broad lowland plains...

Key components of biodiversity cannot be treated equally due to the limitations of resources available for conservation. Therefore biodiversity should be prioritized in effective conservation and site based conservation is one such model to achieve that. However parameters related to ecology, sociology and economics (aka. tourism) are primarily use...

Human-monkey conflicts reached crisis proportions in Sri Lanka over the last 10 years due to extensive deforestation to promote rapid economic growth and agricultural expansion. This resulted in complaints from the public with demands for Sri Lanka’s Department of Wildlife Conservation (DWC) to solve the problem without delay. Caught between politi...