How biodiversity loss jeopardizes human health
Context- Animals, plants, fungi — biodiversity holds a treasure trove of chemicals that can be used to treat disease from malaria to cancer. But its loss is driving species to extinction, dashing many hopes for medicine.
Bright reds, yellows and blues — the colour of poison dart frogs offer a stark warning to curious predators. The amphibians are toxic. When eaten, the chemicals on their skin can cause convulsions, muscle contractions and even death.
(Credits- WorldAtlas.com)
For humans, these colours mean something more hopeful. Those same poisonous chemicals could provide the key to medications that treat infections now resistant to the antibiotics we have already developed.
Basis for much needed medicine
- Natural compounds found on frogs, plants and many other species provide the basis for many of our medicines. Paclitaxel, a drug used to treat cancer, for example, is derived from the bark of the Pacific yew tree, and ziconotide, a drug that is used to treat severe pain comes from cone snails.
- Around 70% of cancer medications are based on nature, according to the UN’s Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).
- But biodiversity, which includes the plants, animals, fungi and bacteria found on Earth, are disappearing — and so, too, are the possibilities they hold.
Human-driven extinction
- Around 1 million animal and plant species are currently estimated to be threatened with extinction, according to a 2019 report published by IPBES, although estimates vary wildly according to the source.
- Experts say species are disappearing 1,000 to 10,000 times faster than the normal rate of extinction and that humans are to blame.
- Since 1990, around 420 million hectares of forest — an area almost the size of the European Union — has been lost — turned into farmland and cleared for other uses. Meanwhile, fish stocks are also diminishing, with figures from 2017 estimating that we’ve overfished a third of global stocks.
- Human-driven climate change is also having an impact. Growing carbon dioxide levels are leading to increased ocean acidification, bleaching corals and destroying vast habitats. Rising temperatures and unsustainable harvesting are also pushing some plant species to the edge of extinction.
Traditional medicine
- While the loss of biodiversity is making it more difficult to discover new medications, it is also affecting how communities access traditional medicine.
- An estimated 4 billion people still rely primarily on natural remedies to heal themselves — whether it’s using latex from fig trees to treat intestinal parasites in the Amazon or neem oil to treat skin disorders in India.
- Around 40% of the world’s plant species are threatened with extinction, according to a report published by the Royal Botanic Gardens, Kew, in London, which is home to one of the most diverse botanical collections in the world.
- Among the threatened plants are 723 species that are used medicinally. The Pacific yew tree — the source of the paclitaxel, the chemotherapy drug, is now classified as near threatened under the IUCN Red List, which tracks the status of different species.
The future of drug discovery
- William Gerwick, a professor at the University of California San Diego, is investigating the symbiotic relationship between the weaver shrimp and cyanobacteria.
- The shrimps weave the bacteria into nests, which provide protection from predators because of the toxic molecules the bacteria produce — molecules that have potential as a treatment for pancreatic cancer in humans.
- “If we lose biodiversity, we’re losing access to molecules that we know nothing about. And some of those molecules might be compounds that would save the life of one of our children from an infectious disease, from cancer.”
Conclusion- Human health and planetary health are intricately intertwined. Beyond drug discovery, we rely on trees to take pollutants, like carbon dioxide, out of the air. We need working wetlands to keep water clean and we need insects to pollinate our crops to provide us with food. Hence Biodiversity conservation should be high on the agenda.
Syllabus- GS-3; Biodiversity
Source- Indian Express
