On the conservation of species

In the 1970s, outbreaks of the grassy stunt virus in rice were decimating yields of the staple food across South and Southeast Asia, threatening the livelihoods of millions. Breeders raced to screen 7000 populations of rice and its close relatives for resistance to the virus. As fate would have it, one population of Indian rice was found to be resistant, and scientists succeeded in breeding its resistance trait into commercial rice varieties. This example is just one of the many reasons why we should worry about the loss of biodiversity.

At this juncture, it is important to unpack what is meant by biodiversity, because public awareness of the biodiversity crisis centres on species diversity — the number of species in an ecosystem or across the biosphere. This is where terms like “critically endangered” and “extinct” come in to describe the risk that a species will disappear from its natural habitat. However, there are two other levels of biodiversity that are just as important but rarely given attention. Genetic diversity looks at the genetic differences within and between populations. It is an indicator of the adaptive potential of a species, and its ability to survive changes to its environment. Hence, if one population of a species becomes extinct, then the species may have lost some of the genetic diversity that makes microevolution possible, making it less resilient. The third level of biological diversity is ecosystem diversity, or the variety of ecosystems on Earth.

Modern societies are obsessed with growth. Increasingly, a thriving economy has become the single yardstick to measure the prosperity and livability of a country. This has serious ramifications for the environment, because the only way to produce more is to take more, to take from the one who has never expected anything in return — Mother Nature.

As demand for beef grew worldwide, Brazil’s then-president, Jair Bolsonaro, cheered silently as violent and corrupt organisations pushed into indigenous lands, into nature reserves and into the lungs of the world. After sacking key environmental officials and slashing funding for enforcement, the message that Bolsanaro was sending out had never been clearer: the Amazon is open for business. At current rates of deforestation, 27% of the Amazon will be without trees by 2030. Deforestation is a severe problem elsewhere in the tropics too, where more than two-thirds of the human population live and where population growth is the fastest. About 63,000 km² of tropical rainforest are cleared each year; that is forest two times the size of Singapore being cut down every week. Global warming aside, as forests disappear, so do large numbers of plant species. There are practical reasons to be concerned about the loss of plant diversity. So far, we have explored the potential uses of only a tiny fraction of the more than 325,000 known plant species. For instance, just six crops — maize, rice, wheat, potatoes, cassava, and sweet potatoes — account for 80% of all the calories consumed by humans. And fewer than 5000 plant species have been studied as potential sources of medicines. Even so, a quarter of prescription drugs in the United States contain an active ingredient from plants. Aspirin, derived from willow bark, is a pain reliever. Menthol, found in eucalyptus trees, is a throat soother. Vincristine and vinblastine, extracted from the rosy periwinkle, are used to treat two deadly forms of cancer, Hodgkin’s lymphoma and childhood leukemia, resulting in remission in most cases. And as Tu Youyou screened ancient Chinese remedies in search of an anti-malaria drug, she stumbled upon an effective compound distilled from sweet wormwood, with its preparation detailed in a 1600-year-old manuscript. Artemisinin-based combination therapies are now standard treatment worldwide for malaria. The tropical rainforest is a treasure trove of healing plants that could become extinct before we even know they exist, let alone get to study them.

Before succumbing to the irresistible opportunity to continue exploiting the biosphere of its resources, it is critical that we realise the countless ways through which natural ecosystems help sustain human life. They detoxify and decompose our waste and reduce the impacts of extreme weather. The organisms in nature pollinate our crops, control pests and create and maintain our soils. In 1997, scientists tried to put a price tag on these ecosystem services. They estimated its value to be $33 trillion each year, more than twice the gross national product of all the countries on Earth at the time ($18 trillion).

Fundamentally, humans also have an innate sense of connection to nature and all forms of life. Moreover, the belief that other species are entitled to life and should be treated with respect is a pervasive theme in many cultures and religions. Together with concern over the state of the planet when it is inherited by future generations, these perspectives form the basis of a moral argument that we should protect biodiversity. Indeed, everyone should be on Team Biodiversity.

There is reason to be optimistic, because the tenacity and determination of biologists, researchers, activists and lawmakers have helped Team Biodiversity score crucial victories. In 1987, an agreement was initiated that reduced Costa Rica’s international debt in return for land preservation in the extremely biodiverse Central American nation. The country has now become a world leader in establishing zoned reserves, an extensive region that includes a protected area surrounded by a buffer zone that prevents further intrusion into the undisturbed core. A 2003 analysis of land cover change between 1960 and 1997 showed negligible deforestation within Costa Rica’s national parks and a gain in forest cover in the 1-km buffer around the parks. However, beyond that, significant forest loss was observed, threatening to isolate the protected areas and diminish their functionality as a collective network. This exemplifies the tension between economic development and environmental conservation. If you were the state governor, would you prioritise the construction of a hydroelectric dam that could provide abundant energy and control devastating floods, or protecting endangered species in the river ecosystem? If you were leading the Urban Redevelopment Authority, would you rather allocate our limited land to developments that can generate jobs and provide housing for your residents, or to green spaces? If you were the owner of a coffee plantation, would you be willing to sacrifice production capacity by also growing trees that support large numbers of songbirds? These questions seem almost rhetorical to most governments and business owners.

Hence, conservation efforts increasingly strive for a win-win outcome: to protect both endangered species and jobs or other aspects of a region’s economy. This is challenging, but not impossible. In the Florida keys, protection of coral reefs where fish spawn has also caused harvests in nearby fisheries to rebound. The rejuvenating marine life within the sanctuary has also made it a favourite among recreational divers, increasing the economic value of this zoned reserve.

With our votes and voices, everyone has a part to play in this collective fight. Let’s make the right choices, fix our mistakes, and protect the gem that is biological diversity. There is reason to be optimistic.

References

1. Campbell Biology 12th edition Chapters 30 & 55

2. Matt Sandy. Why is the Amazon rainforest disappearing? Time Magazine, The Tipping Point. Why Is the Amazon Rain Forest Disappearing? | Time

3. G. Arturo Sánchez-Azofeifa et al. (January 2003). Integrity and isolation of Costa Rica’s national parks and biological reserves: examining the dynamics of land-cover change. Biological Conservation, 109(1). https://doi.org/10.1016/S0006-3207(02)00145-3

Image Credit:

1.  https://www.shutterstock.com/search/conservation-globe-animals