The Anthropocene extinction
The Anthropocene (holocene) extinction is the ongoing sixth mass
extinction, and is considered to the most serious environmental threats that
we are facing. Around 150 species go extinct each day. Most researchers
estimate the extinction rate right now to be between 100 and 10,000 times
the background extinction rates, which is around 1 to 5 species a day.
How can we de-extinct?
Back breeding: back breeding is selectively breeding animals in order to
get a phenotype similar to their extinct ancestors.
This was used to resurrect quaggas, by selectively breeding zebras, their
close relatives.
This isn't the best method because it is essentially a different species with
similar phenotypes. Moreover, a closely related species is required to use
this method and therefore may not be possible for long extinct animals.
And it may take a very long time. Nonetheless, when combined with other
methods such as genome sequencing and in vitro fertilization can prove to
be very useful.
Cloning: Cloning is the process of producing individuals with identical or
virtually identical DNA.
We have been cloning animals including sheeps, camels, dogs and other
animals since 1996 when dolly the sheep was cloned. The first ever animal
that was resurrected, the Pyrenean ibex was resurrected using cloning. But
the baby ibex died, almost immediately, because it's lungs failed to function.
However, this method hasn't been perfected. It also requires the complete
DNA, so it isn't possible for most long extinct species yet.
Genetic engineering: Genetic engineering using CRISPR-cas9, essentially
a type of pre-programmed scissors for molecules, can be used to edit DNA
, so strands of DNA can be added or removed at specific points.
This can be used to insert genes from extinct animals into the DNA of
closely related species creating a hybrid with phenotype of the extinct species.
Scientists are trying to resurrect preserved mammoths by adding genes to
the DNA of the closely related species such as the Asian Elephant.
Why should we de-extinct?
● Resurrection can help in increasing biodiversity.
● It can be educational and solve many scientific mysteries.
● Some species might have medical uses.
● There might be a moral obligation to bring back the species that
have been extinct because of human activity.
● It can help in fixing the disrupted food chains and webs.
● Species such as woolly mammoths can help with fighting climate
change by increasing grasslands. (May help in other environmental
problems as well).
Why we shouldn't de-extinct?
● A long extinct species may not be able to adapt to the new
environment.
● They may disrupt new ecosystems.
● It may outcompete species that developed in its absence.
Conclusion
Once the de-extinction methods are perfected, recently extinct species
should and can be resurrected by storing their DNA, on the contrary more
research will have to be conducted to find out if the long extinct species
can survive in the newer ecosystems and if they should be resurrected.
References:
- Lakshee Karle (laksheek11@gmail.com)