Biodiversity Hotspots

Biodiversity Hotspots

Subject – Environment

Context – Jackie Chan, Balerion and Smaug inspire names of gecko species described from Western Ghats

Concept –

• Researchers have described 12 gecko species from the Western Ghats, ten of which are found nowhere else.
• The geckos were given some creative names, including a quick and nimble species named after martial arts superstar Jackie Chan, a couple named after fictional dragons, and one named after the cosmos.
• The quest to find geckos was part of a larger survey to document the diversity of the frogs, lizards and snakes of the Western Ghats and to search for critically endangered species in the diverse region.
• The Western Ghats have been identified as a biodiversity hotspot and there are many protected areas in the region, but a growing human population is putting pressure on the unprotected habitats through expanding urban areas, logging, dams, and the spread of agriculture.

About Biodiversity Hotspots –

• Biodiversity hotspots are regions with high species richness and a high degree of endemism.
• The British biologist Norman Myers coined the term “biodiversity hotspot” in 1988 as a biogeographic region characterized both by exceptional levels of plant endemism and by serious levels of habitat loss.
• Conservation International (CI) adopted Myers’ hotspots and in 1996, the organization made the decision to undertake a reassessment of the hotspots concept.

• According to CI, to qualify as a hotspot a region must meet two strict criteria:
  • It must contain at least 1,500 species of vascular plants (> 0.5% of the world’s total) as endemics – which is to say, it must have a high percentage of plant life found nowhere else on the planet. A hotspot, in other words, is irreplaceable.
  • It has to have lost at least 70% of its original habitat. (It must have 30% or less of its original natural vegetation). In other words, it must be threatened.
• The 35 biodiversity hotspots cover 2.3% of the Earth’s land surface, yet more than 50% of the world’s plant species and 42% of all terrestrial vertebrate species are endemic to these areas.
• In 2011, the Forests of East Australia region was identified as the 35th biodiversity hotspot.

Biodiversity hotspots in India

• Himalaya: Includes the entire Indian Himalayan region (and that falling in Pakistan, Tibet, Nepal, Bhutan, China and Myanmar).
• Indo-Burma: Includes entire North-eastern India, except Assam and Andaman group of Islands (and Myanmar, Thailand, Vietnam, Laos, Cambodia and southern China)
• Western Ghats and Sri Lanka: Includes entire Western Ghats (and Sri Lanka).
• Sundalands: Includes Nicobar group of Islands (and Indonesia, Malaysia, Singapore, Brunei, Philippines).

Note –

Eastern Himalayas, was originally part of the Indo-Burma Biodiversity Hotspot. In 2004, a hotspot reappraisal classified the region as part of two hotspots: Indo-Burma and the newly distinguished Himalaya.

Range Shifts –

• As temperatures rise, some plants and animals are experiencing range shifts, or movement to higher elevations and cooler habitats.
• Range shifts are usually defined as changes of the distribution limits of a species, generally along altitudinal or latitudinal gradients.
• Range shift is a relatively well-understood response to climate change, but our ability to predict shifts is limited.
• Two factors that may cause variation in range shifts across species are dispersal ability and varying rates of climate change through time and across space.