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https://theconversation.com/nzs-unique-fossil-record-of-marine-molluscs-helps-scientists-predict-extinction-risk-before-its-too-late-285783>
"Scientists are increasingly worried we may be witnessing the start of the
“sixth mass extinction” – the first to be caused by human activities.
Five earlier mass extinctions, caused by dramatic but natural events, have
devastated life on Earth during the past half billion years.
The most famous, though not the largest, was triggered by an asteroid impact 66
million years ago and caused the demise of the dinosaurs – with the exception
of a feathered, meat-eating group that continued to evolve into modern birds.
Today, the rapidly increasing rate of human-caused extinctions is one of our
greatest challenges.
To slow these accelerating rates, we need to understand and minimise the
factors that raise extinction risk. But therein lies a problem. Although
predictable to some extent, extinction is subject to fickle outcomes and can
only be truly understood in hindsight, when it is too late.
For example, the spectacularly abundant passenger pigeon in North America –
likely the most abundant bird on the planet at the time – was driven to
extinction within a few decades during the 19th century.
In contrast, the tuatara persisted for 80 million years in New Zealand as the
last vestige of a group of reptiles that were formerly globally widespread and
abundant.
Extinction risks are relatively easy to predict in highly visible and
well-studied species such as the blue whale and New Zealand’s flightless night
parrot kākāpō. They are very hard to predict in myriad marine invertebrate
species that keep ocean ecosystems functioning.
But that is where New Zealand is uniquely placed to quantify and predict marine
extinction risks, using the fossil record. We can quantify a growing
“extinction debt” – a measure of the number of species committed to future
extinction because of human actions today – and act on that before the debt is
locked in."
Cheers,
*** Xanni ***
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mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
