Nature - who needs it?

We are currently destroying species at a rate 100 times faster than ever before in history, and each uniquely adapted organism lost takes with it a potential benefit for human health.  

"If the owl can't adapt to the superiority of humans, screw it... I know that sounded heartless. But If a spotted owl can't adapt, does the earth really need that particular species so much that hardship to human beings is worth enduring in the process of saving it? Thousands of species that roamed the earth are now extinct. Do you hear anyone making the case that the earth would be better off if dinosaurs were still roaming the planet? – Rush Limbaugh

Heartless indeed, not to mention crudely expressed, yet even so this viewpoint – that species other than Homo Sapiens must adapt and prove their worth to us or die – still enjoys considerable support.

If you love nature, you don’t need convincing that species loss is undesirable. You want earth’s scintillating treasure trove of organisms kept intact for its own extraordinary sake.

But such sentiments will not sway hard hearts of the Limbaugh persuasion. Nor will they sway many others more left-leaning, who feel that in a resource-strapped world it’s wrong to lavish attention on the Black-breasted Puffleg while humans go hungry.

And, truth be told, even ardent nature-fanciers may sometimes secretly harbour the blasphemous thought: “What has the Black-breasted Puffleg ever done for me and will I really miss it when it’s gone?”

Wonderful Life. "Cattleya Orchid and Three Hummingbirds". (Martin Johnson Heade, 1871)

Dazzling diversity
Current estimates of the total number of species on earth range from 5 million to 30 million, about 1.75 million of which have been documented. In the past year or so alone, over 1000 new species were identified. Do we really need to conserve every last one of them?

International biodiversity experts such as those who met recently for the 2009 Diversitas: Biodiversity and Society conference in Cape Town, would answer with a resounding Yes.

CSIR systems ecologist Bob Scholes explains that although scientists are aware of many of the negative effects of species loss, it's also the losses and impacts they don't know about that are worrying, and these are happening at an unprecedented rate.

"Extinctions have always happened, that’s true, but what’s changed is the rate at which it’s happening: we're losing species at least 100 times faster than ever before,” said Scholes.

But despite terrifying stats such as this, conservationists still often need to hard-sell the idea – of endangered species' inestimable value – to doubters and the indifferent.

Luckily for biodiversity-huggers, plants and animals (and not just obvious ones like sundried tomatoes and Karoo lamb, but the puff-legs of the world) have highly utilitarian potential that we’ve only just started to tap.

Beyond fine dining, cuddly pets and pretty gardens, plants and animals perform vital “ecosystem services”, interacting with each other and the inorganic environment in a subtle, elaborate dance that gives us fresh food, potable water and breathable air. Scientists have only a vague understanding of what happens whenever one of the dancers disappears, but numerous case studies show that the consequences are frequently dire, and more so the higher the disappearance rate.

We can’t exist at even the most basic level without other organisms. And hopes for something more than brute survival i.e. living really well and splendidly and long, may well depend on them too.

As medical scientists Aaron Bernstein and David Ludwig put it, biodiversity provides “a new lens with which to look on human health and disease.”

Mining the treasure trove
Despite huge financial investment in synthetic drug development, 50% of the 100 most commonly prescribed medications, and about 50% of new drugs approved in the past 25 years, have been derived from nature.

You may be familiar with some that have been around even longer, such as penicillin from bread mold and digitalis (used to treat heart conditions) from foxglove.

Unlikely treasure: bread mold. (Photo: Henry Mühlpfordt)

But you may not yet have heard of some of the newer finds, like vincristine from the Madagascan rosy periwinkle, used to treat childhood leukaemia. Or paclitaxel from the bark of the Pacific yew tree, employed to shrink tumours and keep arterial stents clear. Or ziconotide, a painkiller 1000 times more potent than morphine, derived from sea-snail venom.

The beauty of nature’s pharmacopoeia is that, because we all evolved on the same planet, humans and other organisms often have biochemical similarities. A neurotoxin that a spider uses to disable the relatively simple nervous system of a fly, for example, may well act on the more complex, yet still comparable human system, to control Parkinson’s. And these physiological processes have been tried and tested and refined down through the ages by the rigours of natural selection.

So nature is full of potential new cures. But not only that: it’s bursting with ideas.

Endless forms, flawless functions
Scientists are also realising how much we have to gain by observing the myriad ways organisms are adapted to their specific environments and roles.

Nature has had a long, long time to perfect form and function, and scrap faulty models. The result is an almost limitless array of solutions and systems – from the perfect aerodynamism of a humpback's fin, to the internal cooling system of a termite mound – far more elegant and efficient than any we’ve come up with.

The field of biomimetics (also sometimes called bionics) is engaged with copying these ideas and applying them for human use.

The most famous example of biomimetics (and probably the most commercially successful to date) is Velcro: its inventor got the idea when picking burrs off his dog’s coat.

Applications for human health and wellbeing are burgeoning. To take just a few of many fascinating examples:

• The sandcastle worm builds a shelter in the surf by secreting a powerful glue that bonds wet items like sand grains and sea shell fragments. Scientists have duplicated the glue, creating a medical adhesive to repair shattered bones in the “wet” environment of the body. Studies are underway to allow the adhesive to simultaneously deliver drugs such as antibiotics to the fracture site. Other medical adhesives involving glue and tiny hairs are being developed based on structures found in gecko feet, which allow these animals to effortlessly scale vertical surfaces.
• Natural adaptations to arid environments offer solutions in an increasingly water-starved planet. A beetle that lives in the Namib Desert, for example, has alternately waxy and non-waxy patches that promote the formation of water droplets, which the insect drinks. The thorny devil, a lizard native to the Australian outback, rapidly soaks water up from the ground through its skin, and "wicks' it towards its mouth. Scientists are looking for synthetic materials to duplicate these models, which could help with water collection for human use in drought-stricken regions.
• Pinecones, which respond to temperature increases by opening their scales to disperse their seeds, have inspired a design for “smart” clothing. The fabric imitates the pinecone scales, opening when warm, and closing when cold.

Animals in their natural environments may also serve as valuable research models for human health: 

Polar bears could teach us how to elude osteoporosis, kidney disease and diabetes. (Photo: Ansgar Walk)

• Polar bears don't lose bone mass during months of immobility during hibernation, as all other mammals would - including ourselves. They also don't urinate during this period. And, although they become hugely obese in preparation for their long sleep, they don't develop Type II diabetes, as obese humans often do. Study of these animals may uncover novel ways to treat to common human scourges of osteoporosis, kidney failure and obesity-related diabetes.
• Certain long-lived animals like rockfish (centenarian examples of which have been found on dinnerplates), and others even closer to us like sea turtles and bow-head whales (both of which can live over 200 years), display "negligible senescence" – very slow or negligible aging. Medical gerontologists believe that studying them may reveal vital clues to improving our own longevity.
• Sharks seldom develop cancer. They may produce a compound that inhibits tumor growth by constricting the surrounding blood vessels – a technique scientists think holds one of the most promising ways to battle cancer in humans.

But of course polar bears and sea turtles are in short and dwindling supply, along with all those other organisms stressed by our rampant exploitation of the place we’re meant to be sharing with them. Each one that winks out forever takes with it its unique brilliance, and the secrets it might have told us. The world probably won't end when the Black-breasted Puffleg does, but it will certainly be left poorer.

(- Olivia Rose-Innes, EnviroHealth Editor, Health24, October 2009)

Long-lived creatures like this green turtle may hold the secret to extending youth. (Photo: Mila Zinkova)

Notes:
- The Black-breasted Puffleg (Eriocnemis nigrivestis) is a species of critically endagered hummingbird found only on the northwestern slopes of the Pichincha volcano in Ecuador. It was chosen for this article to represent the unique, obscure and increasingly beleaguered creatures of the world (primarily because of its unique, obscure name).
- Rush Limbaugh is an American right-wing radio personality who makes deliberately provocative statements, and actually seems to believe most of them.

References:
Bernstein, A and Ludwig, D. The Importance of Biodiversity to Medicine. Journal of the American Medical Association. 2008;300(19):2297-2299.
Chivian, E and Bernstein, A (Eds). Sustaining Life: How Human Health Depends on Biodiversity, 2008.
Guerin, J. Long-lived Animals with "Negligible Senescence": Emerging Area of Aging Research. Anti-Aging Medical News. 2001.
HealthDay News Sea worm glue for fractures August, 2009.
Limbaugh, R. The Way Things Ought To Be. 1992.