Reviving Extinct Species: Conservation's Controversial Path
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The alarming truth is that numerous species are disappearing from our planet, while some, like the Giant Panda, are making a comeback. But why should we be concerned?
Typically, we lose between one and five species to extinction annually. However, a recent study has revealed that this rate is escalating dramatically, with several species vanishing each day. Currently, around one million plant and animal species face extinction, and projections suggest that by 2100, half of all species on Earth could be lost. This swift decline in biodiversity has prompted scientists to label this phenomenon as the sixth major extinction event.
Reflecting on past extinction events, we note the Ordovician-Silurian extinction roughly 440 million years ago, the Devonian extinction around 365 million years ago, the Permian-Triassic extinction approximately 250 million years ago, the Triassic-Jurassic extinction about 210 million years ago, and the Cretaceous-Tertiary extinction 65 million years ago, which led to the demise of the dinosaurs.
Fossil records offer insights into the causes and repercussions of previous mass extinctions, often linked to extreme fluctuations in temperature and sea levels, or singular events such as volcanic eruptions or asteroid impacts.
While mass extinctions are not unprecedented, the current crisis is unique because it is primarily instigated by one species: humans.
The irony lies in the fact that our survival hinges on the very ecosystems we are disrupting and the species we are driving to extinction. This is not a simple regression; it is a ticking time bomb, making it impossible to foresee the full ramifications of the chain reactions we ignite daily.
For instance, if the tundra melts or if methane hydrates beneath the oceans are released, significant amounts of methane would enter the atmosphere. While climate change is already a pressing issue, methane is 25 times more potent than carbon dioxide as a greenhouse gas. This is one climate crisis we want to avoid triggering.
The climate crisis and biodiversity crisis are interconnected, yet distinct.
It’s crucial to remember that biodiversity loss directly impacts us. We are part of this system, and everything is interlinked. The loss of species disrupts ecosystems that, in turn, support us directly or indirectly. This can lead to coastlines becoming more susceptible to flooding and storm damage due to the decline of coral reefs and mangroves, diminished access to food and medicine because of rainforest degradation, or reduced pollination from declining bee populations, which would severely impact agriculture. In essence, our very survival is at stake.
As we lose species at an alarming rate, we also forfeit the chance to learn from them. There remains much we do not understand about animal behavior and ecology, and losing these species before we gain full insight means we might miss the opportunity to conserve them and, by extension, ourselves.
Take whales, for example; they play a vital role in marine ecosystems. They help circulate nutrients throughout the oceans, supporting phytoplankton that absorb nearly one-third of human-generated carbon dioxide and provide over half of the world’s oxygen. Despite efforts to protect them, whale populations still face substantial threats from climate change, which disrupts migration patterns, as well as human-induced dangers such as fishing boats and plastic pollution.
In India, the rapid decline of vulture populations due to drug poisoning linked to livestock management has led to unexpected increases in disease spread. Vultures are essential scavengers, and their absence has allowed other scavengers, like feral dogs and crows, to proliferate, exacerbating public health issues and prompting urgent conservation efforts.
What other unforeseen consequences might we face?
There are known knowns—things we know we know. There are known unknowns—things we know we don’t know.
— Donald Rumsfeld
So, how do we address these challenges and prevent impending climate and biodiversity disasters?
Should we drive less, reduce plastic use, or decrease meat and fish consumption?
What if we could simply bring extinct species back to life?
De-Extinction
De-extinction refers to the process of reviving organisms that are either functionally extinct or have already vanished. Various methods exist to achieve this, including back breeding and cloning, which have been utilized for some time. Recent advancements in stem cell technology and gene editing techniques, such as CRISPR-Cas9, show promise. By integrating DNA from extinct species with the DNA of existing species, we may create hybrids that exhibit traits of the extinct organisms, potentially leading to viable populations.
As technology progresses, sequencing the DNA of extinct species from older and more degraded samples is becoming increasingly feasible. However, DNA degrades over time, presenting challenges to reviving species.
The de-extinction process involves two significant steps: first, creating the living organism, which has become more achievable with CRISPR technology, and second, successfully reintroducing the species into the wild. This latter step is complex, as species do not exist in isolation. The reintroduction of apex predators or unfamiliar prey into ecosystems that may have been filled by other species complicates predictions about the impacts on food chains and ecological balance.
But is it worth it? What motivates the drive to resurrect extinct creatures?
Which Species Could Be Revived and Why?
Several candidates for de-extinction are being considered. Here are a few notable examples:
- Pyrenean Ibex: This species went extinct twice in the last two decades. After the last individual was tragically killed by a falling tree in 2000, scientists used preserved DNA to create a clone. While the cloning attempt was successful, the individual survived only ten minutes post-birth. Currently, the project appears more about demonstrating technology than genuine recovery.
- Woolly Mammoth: Scientists have sequenced mammoth DNA from 4,300-year-old samples in Alaska and 44,800-year-old samples from Siberia. Utilizing CRISPR to insert mammoth genes into Asian elephant cells and possibly employing 3D-printed artificial wombs for gestation, researchers aim to resurrect the woolly mammoth. This effort seeks to restore the 'mammoth steppe' in northern Russia, which could help mitigate permafrost thaw and climate change.
- Passenger Pigeon: Once the most populous bird on the planet, the passenger pigeon vanished about a century ago. Its vital role in forest ecology is only now being appreciated. Revive & Restore aims to incorporate passenger pigeon DNA into band-tailed pigeons using genetic editing and selective breeding. The goal is to reintroduce this species to its native habitats, restoring ecological functions. Plans suggest that hybrids may be ready for breeding by 2024 and release by 2030.
Is De-Extinction a Sound Approach?
Now that we have contributed to the extinction of numerous species, is our desire to bring them back driven by human ego, or is it a moral obligation to rectify our ecological wrongs?
Proponents argue that if successful, de-extinction technology could preserve genetic diversity and safeguard species on the brink of extinction. Reviving species that play crucial roles in habitat management could facilitate more effective conservation efforts. Some even view it as a moral responsibility to amend the ecological damage we’ve inflicted.
However, critics raise significant concerns. De-extinction is an expensive pursuit, sometimes costing over $10 million. Many believe these funds could be better allocated to conservation efforts aimed at preventing extinction in the first place. Additionally, the availability of de-extinction as a solution may inadvertently endorse extinction and biodiversity threats. Others argue that intervening so heavily in nature contradicts conservation principles and that reintroduced organisms might not thrive in modern ecosystems.
Furthermore, there is no assurance that these revived species would survive in today’s environmental conditions, given the potential for new diseases and threats. Reviving a species could disrupt existing ecosystems or species, leading to unforeseen consequences.
Will De-Extinction Be Successful?
Beyond ethical debates, numerous technological challenges remain before we can anticipate seeing woolly mammoths roaming the plains or passenger pigeons soaring through the skies again.
Conservation is indeed a race against time. With the climate crisis and unprecedented biodiversity loss, we have initiated a cascade of events that could render the planet inhospitable for life as we know it. We may struggle to protect our own species from extinction, let alone find time to revive others.
Ultimately, the success of any de-extinction or conservation initiative hinges on our ability to act as better stewards of the Earth and its remaining habitats. Given our current handling of the climate crisis, it remains uncertain whether we can learn from these challenges and take the necessary actions to secure our future.