Yasuni, Ecuador - Biologist Phylis Coley and her husband, Tom Kursar, have devoted their working lives to the study of plants, and nowhere is it more fascinating, they say, than in Ecuador's Yasuni National Park - the most biodiverse place on the planet.

"Evolution is going incredibly fast here with the plants evolving as quickly as they can and the herbivores counter-evolving. It's a never-ending escalation," Coley told Al Jazeera. They call it an "arms race". On one side the plants; on the other, insects and other herbivores. Each of them evolving defences to outwit the other.

In Yasuni, a single hectare of rainforest is home to more than 100,000 species of insect. In this tropical climate without a winter to knock back the insect population, "the diversity of insects is extremely high, and so this 'arms race' is running at a much faster rate. It's much more intense than anywhere else in the world", said Coley.

"Each plant is defended by a variety of strategies, including toxic compounds that limit the number of herbivores that can actually feed on it," she adds.

The baby leaves, which are targeted because they are higher in protein and nutrients than the mature ones, are the focus of their study.

"The young leaves are heavily attacked by everything, and so they've been under very strong selection to evolve a whole battery of defences. They make nectar to attract ants, which are pugnacious bodyguards. They can grow very quickly. But their biggest defence is being full of toxins. So an individual baby leaf is about 50 percent dry weight of these poisonous toxins," Coley said.

This forest is probably full of compounds that would have enormous value for a whole variety of human health issues. - Phylis Coley, biologist

Plant saviours?

It was this fact that led the pair from the University of Utah to the conclusion that the plants themselves could be key to saving rainforests such as Yasuni, under threat from extraction and exploitation.

"This forest is probably full of compounds that would have enormous value for a whole variety of human health issues," Coley said.

Kursar insisted that bio-prospecting - as it's called - "can help save the environment by providing an alternative to the other various forms of use, such as logging, ranching and oil".

A year ago, Ecuador's President Raphael Correa gave the go-ahead for further oil extraction from beneath another area of the Yasuni, known as the Ishpingo-Tambococha-Tiputini (ITT). That work is now getting under way.

Concerned about the potential impact on the environment and on indigenous tribes, Correa had previously said he would leave the huge oil reserve in the ground - if developed nations paid Ecuador about 50 percent of its value, or about $3.2bn.

When that didn't happen, Correa changed his tune saying, "I insist that we are going to exploit our natural resources, as all countries in the world do. We cannot be beggars sitting on a sack of gold."

He's argued this latest phase of extraction in this still oil-dependent nation will help lift the country out of poverty.

But Kursar and Coley were adamant bio-prospecting can offer a viable, longer-term alternative to oil.

"Obviously the amount of money that can be made very quickly on oil is enormous. But one of the problems with oil is that much of the money goes abroad," Kursar told Al Jazeera. "It's a one-time boom-and-bust philosophy, whereas bio-prospecting is something which takes a little longer to establish, but has the potential to go on indefinitely."

Nature's 'pharmacy'

Coley added: "Right now, about 30 percent of the prescription medicines that we use come from nature, despite all the pharmacological techniques we have. And yet we've really not looked at all in tropical rainforests, which is where we would expect the diversity and the potential of these chemicals to be the greatest.

"And nowhere in the world has this pharmacy got more potential than here in the Yasuni area of Ecuador."

They already have a project under way in Panama where they managed to convince the government it was worthwhile, because of immediate benefits such as jobs and training.

That programme, called the International Cooperative Biodiversity Groups (ICBG), analysed organisms - including plants and micro-organisms from marine and terrestrial habitats.

"We have several patents, including promising leads for cancer and malaria," said Coley. "The Panamanian scientists on the project were also instrumental in making Coiba National Park a [UN] World Heritage Site."

But the biologist team admits with no guarantees that medical discoveries will be made quickly, it can be a tough sell to governments.

"In terms of replacing many billions of dollars of oil revenues, probably over the long run, if it's done properly, those benefits could be replaced. It's very challenging, but I think it's possible," Kursar said.

Another key challenge is many governments' fear over so-called bio-piracy, in which a foreign scientist will come into a country and remove an organism or compound without permission, and reap the financial benefits.

Pushing ahead

Ecuadorians remain divided by the government's decision to push ahead with more oil extraction in Yasuni, but know little about bio-prospecting. After 40 years of oil extraction in Ecuador, many say the last ones to benefit financially have been the people who live in communities where the drilling occurs.

The town of Coca is one such place. Washington Wilke summed up the feelings of many in Coca who say despite the presence of the oil industry, they still lack many basic services and want to see investment in schools, universities and hospitals.

"I've lived here for 30 years and every time the scale of oil exploitation is bigger, but the development in the communities is little," said Wilke.

However, representatives of Correa's ruling party say this time it will be different. While admitting she, too, is concerned about the environmental impact, Coca's mayor, Anita Rivas from Correa's Alianza Pais party, told Al Jazeera the oil resource must be exploited for the lives of her constituents to improve.

"Are we supposed to sit on top of a gold mine and die?" asked Rivas. "It's a great challenge for our government to show the world that a small oil-producing country can extract oil despite a big risk to the environment. But exploiting oil will allow future generations to leave poverty behind."

And, she said, the bottom line is that Ecuador is still oil-dependent.

I've lived here for 30 years, and every time the scale of oil exploitation is bigger, but the development in the communities is little. - Washington Wilke, Coca resident

Infinite resource

One of the Ecuadorian students working with Coley and Kursar's team is determined to get formal backing for bio-prospecting in the Yasuni.

Maria Jose Endara said: "We have had bad past experience with 'bio-piracy'. These instances have made the issue of bio-prospecting a taboo. But Ecuadorians feel proud of the natural resources we have. Oil is not an infinite resource, and the state oil company would have to keep moving further into the Yasuni to keep extracting oil with the resulting damage to the forest, which is irreversible.

"It is my understanding that the government is willing to provide funding for projects that would change the production matrix of the country - projects that would help to move the country away from oil."

But Endara said she doesn't believe the government will stop its oil extraction of Yasuni. "I see the bio-prospection as a future alternative."

Endara pointed to the discovery of fungi in the Amazon by Yale university students. It can be used to break down the plastic material polyurethane, which is used in the manufacture of everything from toys to aeroplanes. Her hope, though, is that Ecuadorians, themselves, will see the benefits.

"We could also target diseases that are of national interest, such as dengue, leishmaniasis, chagas. Finding a cure for such a disease would be good for our economy," said Endara.