The first Briton to actually get into the canopy may have been Sir Francis Drake who, in 1573, gained his first glimpse of the Pacific Ocean from a tall tree in Darien, Panama. However, the first serious effort to reach and study the canopy didn’t begin until 1929. The Oxford University Expedition to British Guiana, led by Major RWG Hingston, still ended up help of locals when it came to building an observation platform. It was a successful expedition all the same, despite the colony’s acting governor getting stuck high up on a winched seat during a visit. In terms of canopy access, the French have proved themselves to be excellent innovators, taking things further with the development of ‘lighter-than-air platforms -balloons and related equipment, to you and me. Francis Halle; from the Laboratoire de Botanique Tropicale at Montpellier University took to a balloon in the mid-1980s in order to approach the canopy from above. His work in French Guiana was inspired by the use in Gabon of a tethered helium balloon by Marcel and Annette Hladick. Halle went one further by using a small purpose-built airship-a cigar-shaped balloon with propellers to aid manoeuvrability. “We suddenly had a mobile system that could move around the treetops; there were no other means of doing this,” says Mitchell.

The forest canopy – the term given to the aggregated crowns of trees in a forest – is thought to host up to 40 per cent of all species, of which ten per cent could be unique to the forest roof. “We’re dealing with the richest, least known, most threatened habitat on Earth,” says Andrew Mitchell, the executive director of the Global Canopy Programme (GCP), a collection of groups undertaking research into this lofty world. “The problem with our understanding of forests is that nearly all the information we have has been gleaned from just two meters above the soil, and yet we’re dealing with trees that grow to heights of 60 meters, or in the case of the tallest redwood 112 meters. It’s like doctors trying to treat humans by only looking at their feet.”

It appears that the rest of the scientific community has now come around to Mitchell’s way of thinking. “I think most scientists thought him mad to consider such a complex field station at first,” says internationally respected ‘canopist’ Meg Lowman, the executive director of the Marie Selby Botanical Gardens. “However, we’ve all come to realize that a combination of methods, a long-term approach to ecological studies and a collaborative approach are the absolute best ways to advance canopy science. A permanent canopy field station would allow that to happen.” With A dedicated group of canopy scientists working together and a wide range of tools available for them to get into the treetops, we’re now finally on our way towards a true understanding of the least-known terrestrial habitat.

Smithsonian Tropical Research Institute in Panama. Smith had the idea of using a static crane to get into the treetops. Un-tethered balloons may allow widely distributed sites to be sampled, but cranes allow scientists to study an area of at least a hectare from soil to canopy throughout the year, year after year. “Cranes beat any other access mode. They are cheap, reliable and fast. In two minutes I can reach any point in our forest, which is essential for comparative measurements across species,” says Professor Christian Korner of the University of Basel. Korner is using a static crane in a unique carbon dioxide-enrichment experiment in Switzerland, in an attempt to discover how forests might respond to the global increase in atmospheric carbon dioxide (see Swiss canopy-crane carbon experiment, right). For reasons of convenience, cranes are generally situated close to cities or a research center. Leipzig University has a crane not far from the town, the Location allowing scientists to study the effect of city pollutants on forests. In order to increase the amount of canopy a crane can access, some have been mounted on short rail tracks. In “1995, Dr Wilfried Morawetz was the first to use this technique, installing a crane on 150 meters of track in the Venezuelan rainforest. “In my opinion, cranes should be the core of canopy research in the future,” he says.

His third experiment is studying yawning in those with brain disorders, such as autism and schizophrenia, in which victims have difficulty connecting emotionally with others. A psychology professor at the University of Maryland, Robert Provine, is one of the few other researchers into yawning. He found the basic yawn lasts about six seconds and they come in bouts with an interval of about 68 seconds. Men and women yawn or half-yawn equally often, but men are significantly less likely to cover their mouths which may indicate complex distinction in genders.” A watched yawner never yawns,” Professor Provine said. However, the physical root of yawning remains a mystery. Some researchers say it’s coordinated within the hypothalamus of the brain, the area that also controls breathing.

Yawning is an ancient, primitive act. Humans do it even before they are born, opening wide in the womb. Some snakes unhinge their jaws to do it. One species of penguins yawns as part of mating. Only now are researchers beginning to understand why we yawn, when we yawn and why we yawn back. A professor of cognitive neuroscience at Drexel University in Philadelphia, Steven Platek, studies the act of contagious yawning, something done only by people and other primates.

Yawning and stretching also share properties and may be performed together as parts of a global motor complex. But they do not always co-occur – people usually yawn when we stretch, but we don’t always stretch when we yawn, especially before bedtime. Studies by J.I.P, G.H.A. Visser and H.F. Prechtl in the early 1980s, charting movement in the developing fetus using ultrasound, observed not just yawning but a link between yawning and stretching as early as the end of the first prenatal trimester.

For his second experiment, he put 10 students in a magnetic resonance imaging machine as they watched video tapes of people yawning. When the students watched the videos, the part of the brain which reacted was the part scientists believe controls empathy – the posterior cingulate, in the brain’s middle rear.” I don’t know if it’s necessarily that nice people yawn more, but I think it’s a good indicator of a state of mind,” said Professor Platek. “It’s also a good indicator if you’re empathizing with me and paying attention.”

Clinical neurology offers other surprises. Some patients with “locked-in” syndrome, who are almost totally deprived of the ability to move voluntarily, can yawn normally. The neural circuits for spontaneous yawning must exist in the brain stem near other respiratory and vasomotor centers, because yawning is performed by anencephalic who possess only the medulla oblongata. The multiplicity of stimuli of contagious yawning, by contrast, implicates many higher brain regions.

For his second experiment, he put 10 students in a magnetic resonance imaging machine as they watched video tapes of people yawning. When the students watched the videos, the part of the brain which reacted was the part scientists believe controls empathy – the posterior cingulate, in the brain’s middle rear.” I don’t know if it’s necessarily that nice people yawn more, but I think it’s a good indicator of a state of mind,” said Professor Platek. “It’s also a good indicator if you’re empathizing with me and paying attention.”

Yawning is an ancient, primitive act. Humans do it even before they are born, opening wide in the womb. Some snakes unhinge their jaws to do it. One species of penguins yawns as part of mating. Only now are researchers beginning to understand why we yawn, when we yawn and why we yawn back. A professor of cognitive neuroscience at Drexel University in Philadelphia, Steven Platek, studies the act of contagious yawning, something done only by people and other primates.