The Western Ghats is a biodiversity hotspot extending along the west coast
of India. It has a high endemism and harbours over 5000 plant species.
Whereas, the evergreen forests populating the wet zone on the western
slopes have existed since 65 million years ago, the deciduous forests
populating the eastern plateau were established during the Miocene
aridification about 10 million years ago. Additionally, the wet zone also
has a latitudinal gradient in length of dry period that was established
after the intensification of the monsoons and thus affects species
composition, with the relict evergreen species largely confined to the
southern refuge pocket. In this study, we tested the antiquity of the
evergreen forests, the southern refuge hypothesis, and the relationship of
species across these forest types.

We found evergreen forests show antiquity compared to deciduous forests,
and PD patterns corroborates the southern refuge hypothesis. Most
interestingly, deciduous forest species show shared evolutionary histories
with evergreen forest species, suggesting shifts in this trait, whereas
evergreen forests show greater disparate histories possibly due to their
antiquity and sharper gradients in the wet zone.

In many cooperatively breeding vertebrates and primitively eusocial insects individuals choose to remain as helpers throughout their lives despite being capable of independent reproduction. An interesting question that arises is whether such a helping role makes these individuals become reproductively constrained due to ageing and/or helping behaviour (thus are left with the only option of procuring indirect fitness benefits) or whether they can revert back to direct reproduction (and thus gain direct fitness in the future). Here we investigated the effect of age and tasks performed by helpers in the primitively eusocial wasp Ropalidia marginata on their ability for future independent reproduction, by isolating every wasp in the colony and giving them equal opportunity to initiate their own nests and lay eggs. We found that wasps which initiated nests and laid eggs were significantly younger and fed more frequently as adults than wasps which did not initiate nests. However, we did not find any significant influence of the tasks performed by the wasps on their ability to initiate nests and lay eggs. We conclude that ageing and receiving less nutrition rather than working for their colonies, constrain individuals of this wasp species for future independent reproduction. Because future direct fitness and present work towards gaining indirect fitness are not incompatible, we expect to find that although wasps may attempt to gain opportunities for direct reproduction as early as possible, they are nevertheless likely to keep working for the colony until they succeed.

Species diversity shows not only spatial, but also temporal patterns of change. The fossil record retains information of change in communities of species over millions to over thousands of years. Examining such fossil deposits allows for detailed understanding of how individual species and communities of interacting species may have changed over time. This also facilitates our ability to forecast and predict changes in response to future climate change. Fossil deposits, especially those spanning the Pleistocene, are rare in the Indian subcontinent. Using one such small mammal paleo-deposit from the Pleistocene-Holocene from Andhra Pradesh, I will provide a brief introduction to the field of, and the methods in paleo-ecology and what we can learn from looking into the past. I will also discuss the limitations of such datasets, especially from the tropics where degradation is rapid. Despite this, this approach can yield very interesting insights into community responses to long-term ecological and climatic changes.

Participation by Registration only

Recommended for people with experience in generalised linear models. Participation by Registration only

Recommended for people with experience in linear models (e.g., regression, ANOVA). Participation by Registration only.

Participation by Registration only

Participation by Registration only

Participation by Registration only

The Sterile Insect Technique (SIT) consists of the mass-production, sterilization and release of target pest insects in an affected area. Once released, sterile males mate with wild females rendering them infertile. The effectiveness of SIT depends on sterile males performing both pre-copulatory and post-copulatory behaviours in order to compete with wild males. In SIT controlled Tephritid flies, attention has been focused on pre-copulatory behaviours with relatively fewer studies on post-copulatory behaviours such as sperm transfer and the ability of males to inhibit females from remating. Here I review ejaculate dynamics in tephritid flies of economic importance, and focus on the factors that can modulate post-copulatory mating behavior.