Extinction crisis puts one million species on the brink
NATURE is in crisis, and it’s only getting worse. As species vanish at a rate not seen in 10 million years, more than 1 million species are currently on the brink.
Humans are driving this extinction crisis through activities that take over animal habitats, pollute nature and fuel global warming, scientists say. A new global deal to protect nature agreed on December 19 has the potential to help, and scientists are urging the world’s nations to ensure the deal is a success.
When an animal species is lost, a whole set of characteristics disappears along with it - genes, behaviors, activities and interactions with other plants and animals that may have taken thousands or millions - even billions - of years to evolve.
Whatever role that species played within an ecosystem is lost too, whether that’s pollinating certain plants, churning nutrients in soil, fertilising forests or keeping other animal populations in check, among other things. If that function was crucial to the health of an ecosystem, the animals’ disappearance can cause a landscape to transform.
Lose too many species and the results could be catastrophic, leading an entire system to collapse.
In the past five centuries, hundreds of unique animals have vanished across the world, such as the flightless Dodo bird killed off from the island of Mauritius in the late 1600s.
In many cases, humans were to blame - first by fishing or hunting, as was the case with South Africa’s zebra subspecies Quagga hunted to its end in the late 19th century - and more recently through activities that pollute, disrupt or take over wild habitats.
Before a species goes extinct, it may already be considered “functionally extinct” – with not enough individuals left to ensure the species survives. More recent extinctions have allowed humans to interact with some species’ last known individuals, known as “endlings”.
When they go, that’s the end of those evolutionary lines – as occurred in these iconic cases:
■ “Toughie” was the last known individual of the Rabb’sFringeLimbed tree frog. All but a few dozen of his species hadbeen wiped out by chytrid fungus in the wild in Panama. In hisenclosure at the Atlanta Botanical Garden, he was calling out invain for a mate that didn’t exist. He died in 2016.
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