The "Extinctional" crisis

Welcome to the third blog of my blog series on Climate change. In this blog, I’ll be sharing the impact we’re having on the other species of the planet and what’s in there for us.

Click on the words having these colour and fonts for full research study.

You might be familiar with the first image - dinosaurs that went extinct 66 million years ago, the second one being less familiar by image - a dodo who went extinct in 1690 (2 centuries ago) and the last one being a plant - Golden Fuchsia that went extinct in 2020!

According to the UN Environment Programme, the Earth is in the midst of a mass extinction of life. Scientists estimate that 150-200 species of plant, insect, bird and mammal become extinct every 24 hours. This is nearly 1,000 times the "natural" or "background" rate and, say many biologists, is greater than anything the world has experienced since the vanishing of the dinosaurs nearly 65m years ago. Around 15% of mammal species and 11% of bird species are classified as threatened with extinction.

Sources: The Guardian

Right now, many of the species are struggling for survival due to the rapid changes in the climate we are seeing, for a fact – because of the melting of sea ice, all the polar bears will be gone by 2100. And not only polar bears face this threat but many other species are affected by the rapidly changing climate around the world.

Paleontologists characterize mass extinctions as times when the Earth loses more than three-quarters (75%) of its species in a geologically short interval, as has happened only five times in the past 540 million years or so. Biologists now suggest that a sixth mass extinction may be under way, given the known species losses over the past few centuries and millennia. Sources: Researchgate

Scientists don’t know for sure how many species there are on Earth – it could be anything from 2 million to around a trillion! One study estimated that there are around 8.7 million species on Earth today. For an interesting fact, of all the species that have ever existed on Earth, roughly 1% is still alive now. The rest of them (99%) have gone ‘extinct’, often due to unusual climates and natural disasters such as huge volcanic eruptions and asteroid impacts. The most recent mass extinction dates back to 66 million years ago, which famously marked the end of the dinosaur age.

The Current rate of extinction is 1000x faster than the previous ones (calculated using fossils).

Since the 16th century, atleast 680 vertebrate species have gone extinct. This is an output of human induced climate change and the rising temperatures. Currently, the global average temperature is rising faster than ever recorded in the past. If we don’t act now, we could reach temperatures unseen in over 5 million years by as early as 2100.

Some facts and studies:

1. Between 1970-2014, the sizes of over 16,000 vertebrate populations from 4,000 species have declined by 60% on average.

2. One study estimates that 5% of species would be at risk of extinction if the world warms by 2°C, and 16% would be at risk if this rises to 4.3°c – which doesn’t sound good for any species on the planet, even homo sapiens.

3. Heat waves in Australia cause koalas to die due to dehydration as the leaves they eat dry up, while 23,000 flying foxes died from overheating in 2018.

4. Due to rise in the temperatures, the sea levels raise which in turn reduces the habitability near coastal regions resulting in less access to food and living areas.

5. In the rainforest of Puerto Rico, the total weight of arthropods (animals without backbones, including insects) in 2013 was at least 4-8 times less than in 1970s due to them dying due to heat stress. This affects the lizards, frogs and birds which feed on those arthropods resulting in the number of the species of animals other than arthropods themselves.

All this was the result of increase in the average daily temperature by 2°C.

This is not about saving our planet, it’s about saving ourselves. The truth is, with or without us, the natural world will rebuild. In the 30 years since the evacuation of Chernobyl, the wild has reclaimed the space. Today, the forest has taken over the city. It’s a sanctuary for wild animals that are very rare elsewhere. And powerful evidence that however grave our mistakes, nature will ultimately overcome them. The living world will endure; we humans cannot presume the same

- Sir David Attenborough(A life on our planet, Netflix)