Transformative change is needed to prevent over a million species going extinct, according to a new report on the world’s biodiversity.
Based on information gathered over three years from land, freshwater, and marine eco-systems, Earth’s life-support systems may collapse if humanity doesn’t change the way it values and uses nature.
Genetic diversity and food security
Modern livestock breeds and crop species have been bred to be highly productive, which means accentuating particular traits. Chickens have been bred to maintain a uniform size for cost-effective production, while fruits and vegetables have been bred to have thick, juicy flesh. Wild relatives of domesticated plants and animals are the ancestral species from which crops and livestock have descended, or their near relatives. These wild species are thought to be sufficiently closely related to domestic varieties that they could crossbreed to increase their genetic diversity.
The wild relatives of domesticated species inhabit the rocky and icebound fastness of high mountain ranges, dense tropical forests, and arid deserts. They’ve continued to evolve under natural conditions.
Genetic diversity helps species survive long into the future, by increasing the likelihood that individuals will have helpful genetic quirks, such as immunity to a new disease. As climate change makes some growing regions hotter and drier, wild relatives of corn that are drought-resistant could be crossbred with farmed varieties to make them more resilient. As new pathogens emerge, wild relatives of cows could crossbreed with cattle to bolster the immune defenses encoded in their DNA.
Humans are relying on a narrowing base of species for food, using more and more commercially-bred livestock and crops while losing the wild relatives -- the reservoir of genetic diversity.
Protecting wild relatives
The status of wild relatives is worse than for birds and mammals generally. The figures for birds, while overall less threatened, show a similar pattern. It’s perhaps unsurprising given that these species, like their intensively farmed relatives, are large-bodied and so once caught or killed provide a good source of nourishing food. That’s certainly the case for Edwards’s pheasant (Lophura edwardsi) -- a critically endangered species which belongs to the same subfamily as chickens, native to South East Asia and widely snared. A further 30 species are considered endangered.
Losing these wild relatives of domesticated animals seriously threatens the resilience of our food systems. Countries will agree targets for protecting biodiversity in 2020 and the wild relatives of domesticated species should be chief among them.
We really do need a transformation in our relationship with nature, and this will have to include serious change in our diets and how food is produced. We will need wild relatives of important food species to ensure that genetic diversity can enhance food security in an increasingly uncertain future.
Philip McGowan is Senior Lecturer in Biodiversity and Conservation, Newcastle University. Friederike Bolam is Post-doctoral Research Associate in Biodiversity Policy, Newcastle University. Louise Mair is Research Associate in Biodiversity Conservation and Policy, Newcastle University. A version of this article first appeared in The Conversation UK.
