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Time of India
07-07-2025
- Science
- Time of India
Stable forests key to south India's unique biodiversity
HYDERABAD: A mix of stable tropical forests and ancient climate changes led to peninsular India's unique biodiversity over millions of years, according to a study by researchers at the CSIR-Centre for Cellular and Molecular Biology in Hyderabad. Tired of too many ads? go ad free now By examining 33 groups of animals and plants, scientists discovered that some species slowly evolved thanks to long-term ecosystem stability, while others were shaped by drastic changes in climate and landscape between 11 and 3 million years ago. Peninsular India extends from the Aravalli mountains southwards, including the Satpuras and Vindhyas, the Eastern Ghats, the Deccan Plateau and global biodiversity hotspot of Western Ghats. It harbours highly diverse groups of animal and plant species, many of which do not occur anywhere else in the world. The study published in Ecology Letters uncovered how species evolved and disappeared across South Asia and the wider Asian region. By analysing the 33 well-studied groups of animals and plants using mathematical models, the team traced patterns of species formation (speciation) and loss (extinction) across the region. "Each of the groups comprises closely related endemic species and a common ancestor that existed at some point in time. Through millions of years, their descendants spread across the landscape and diversified into multiple species, many of which exist today," said CCMB scientist Dr Jahnavi Joshi. The researchers found a high disparity in how species are formed or lost across groups of animals and plants. They found evolutionarily related groups, such as different kinds of lizards, exhibited similar rates of forming and losing species. Tired of too many ads? go ad free now They also found that half of animal and plant groups accumulated diversity gradually over millions of years. "The stability of the tropical forest ecosystems in Peninsular India has allowed for such steady diversification. As a result, this area has served as a refuge for species from severe climate changes," said Joshi. Pragyadeep Roy, first author of the study, added: "The stability of this ecosystem is surprising given the turbulent geo-climatic past of the landmass. Peninsular India was once part of the Gondwanaland supercontinent with land masses such as Africa and Australia. It broke away 100 million years ago, drifted northward, and collided with Asia, forming the Himalayas. Despite drastic geo-climatic shifts from this movement, the biodiversity changed steadily. This highlights the resilience of its forest habitats." "Global temperatures have been very dynamic across millions of years, and our analysis suggests earth's temperature strongly influences how species are formed in many groups," explained Roy. The study found that some groups experienced abrupt changes in the rates of forming new species within the time range of 11 to 3 million years ago. "This period was marked by high aridification and monsoon seasonality in Peninsular India with a major expansion of grasses, leading to shrinkage of evergreen forests to the Western Ghats and mountaintops of the Eastern Ghats. These events inflicted changes in the ranges and habitats of organisms, disrupting their earlier evolutionary trends," the study said.
New Indian Express
03-07-2025
- Science
- New Indian Express
CCMB study sheds light on species evolution in Asia
HYDERABAD: A recent study by researchers at the CSIR–Centre for Cellular and Molecular Biology (CCMB) has uncovered how species evolved and disappeared across South Asia and the wider Asian region. The study, led by Dr Jahnavi Joshi's lab, was published in Ecology Letters and represents the first large-scale evolutionary analysis of its kind for Asia. Dr Joshi explained, 'Our team analysed 33 well-studied groups of animals and plants using mathematical models to trace patterns of speciation (the formation of new species) and extinction across the region. Each group includes closely related endemic species that share a common ancestor. Over millions of years, their descendants dispersed across landscapes and diversified into the many species we see today.' What makes this discovery particularly striking is the ecological stability observed in the region, despite its turbulent geo-climatic history.
The Hindu
02-07-2025
- Science
- The Hindu
CSIR-CCMB scientists unravel biodiversity changes down south over millions of years
Peninsular India, a tropical region in Southern Asia, extending from Aravalli mountains, Vindhyas, Eastern Ghats, Deccan Plateau, and a global biodiversity hotspot— Western Ghats, harbours unique and highly diverse groups of animal and plant species, many of which do not occur anywhere else in the world. The endemic diversity of the various species could be due to varied trajectories of speciation among different life forms — some due to stability of tropical ecosystems and others by past fluctuations in temperature and geo-climatic changes that occurred between 11 and 3 million years ago, said scientists at the CSIR-Centre for Cellular & Molecular Biology (CCMB) on Wednesday. A recent study from Jahnavi Joshi's lab uncovered how species of life forms evolved and disappeared across South Asia and the wider Asian region by analysing 33 well-studied groups of animals and plants using mathematical models, said an official release. The team traced patterns of species formation (speciation) and loss (extinction) across the region in a broad-scale analysis done for Asia for the first time. 'Each of the groups comprises closely related endemic species, and a common ancestor that existed at some point in time. Through millions of years, their descendants of the common ancestors spread across the landscape and diversified into multiple species, many of which exist today,' explained Dr. Joshi. Researchers found a high disparity in how species are formed or lost across groups of animals and plants. They found evolutionarily related groups, such as different kinds of lizards, exhibited similar rates of forming and losing species. Half of the animal and plant groups had accumulated diversity gradually over millions of years. 'The stability of the tropical forest ecosystems in peninsular India has allowed for such steady diversification. Hence, this area has served as a refuge shielding species from severe climate changes,' she said. Yet, the stability of the ecosystem came as a surprise to the researchers due to the turbulent geo-climatic past of the landmass. 'Peninsular India was once part of the Gondwanaland supercontinent with land masses like Africa and Australia. It broke away around 100 million years ago, drifted northward, and eventually collided with Asia, forming the Himalayas. Despite drastic geo-climatic shifts from this movement, the biodiversity in this region has changed rather steadily. This highlights the fascinating resilience of its forest habitats,' said Pragyadeep Roy, the first author of the study. The remaining half of the groups experienced fluctuating rates of new species forming and losing over time. 'The global temperatures have been very dynamic across several million years, and our analyses suggest that earth's temperature strongly influences how species are formed in many groups,' explained Mr. Roy. The study found that some groups experienced abrupt changes in the rates of forming new species within the time range of 11 to three million years ago. 'The period was marked by high aridification and monsoon seasonality with a major expansion of grasses, leading to the shrinkage of evergreen forests to the Western Ghats and mountaintops of Eastern Ghats. These events certainly inflicted changes in the ranges and habitats of organisms, disrupting their earlier evolutionary trends,' explained the researchers. These insights into how past climate and habitat stability influenced biodiversity can help in devising effective conservation strategies, especially in light of today's anthropogenic activities and climate change. The study was published in Ecology Letters, said the release.
