"You know what your problem is, Dale?" I was once told by a doctor. "It's that you have a size hang-up!" It was a rather insulting statement I thought, and one that caused me to feel a flush of annoyance, requiring some personal effort to conceal. "Once you get over that hang-up though, a new world will open up to you," he continued. "You will see that size is not really of great consequence. Small things truly can be wonderful."

His name was Jon Sullivan, a recent PhD graduate in entomology and he was talking about my lack of interest in his realm of expertise. He was singularly obsessed by invertebrates (animals without backbones), and to be quite blunt, I was not.

The communal dining table at the researchers accommodations in Santa Rosa National Park was strewn with carcasses. Flies, beetles, spiders, wasps, bees and moths littered the white tablecloth between a plate of steaming spaghetti and a slice of frosted chocolate cake. The corpses, recently retrieved from the field, had been emptied out from a cyanide-laced collecting jar, a potentially lethal object which now rested beside Doctor Sullivan's dessert, along with various vials filled with alcohol and deceased creatures.

A light breeze sweeping in from the surrounding forests agitated the assembled dead, causing a few to fall to the floor and vanish beneath the fridge. Three ants became stuck on to the sponge cake, while a hairy fly of some sort landed on top of the spaghetti. The doctor retrieved the escapees under the fridge, plucked out the ants, and then ate the fly on the pasta without noticing.

"Take a look at this, Dale," he said, sliding his microscope over to me. "Isn't it magnificent?" I peered through the two small lenses at a shiny metallic green wasp, desiccated and stiffened by its previous unfortunate inhalation of the good doctor's poisons.

"Now imagine that this thing is as big as a car," he continued as I squinted down. "Walk around it! Look up at it, view it from different angles."

And as I did so, the diminutive insect took on a completely new dimension. Suddenly it was an awesomely beautiful object of incredible design, shining like polished molten metal. Glassy wings, full of complex folds and angles, reflected the light with shimmering rainbows, miniscule but perfectly tuned to create the tiny vortexes needed for aerodynamic lift. Magnification had transformed a microscopic fly into an astounding piece of engineering.

It was in that clear-cut moment that I got over the size hang-up I didn't even know I had.

I've always been fascinated by animals such as jaguars, sea turtles, and dolphins, but invertebrates just didn't cut it - they seemed to me nothing more than flying teeth that bite and pester. Too small to be worth much attention, I tended to overlook them as irrelevant and somewhat boring life forms; insignificants that lead short, dull existences. Insects are either in your soup, up your pant leg or getting themselves wedged into the corner of your eye.

But I have, since then, learned to take a closer look, and to my delight, that fascinating world Doctor Jon Sullivan promised me, did indeed turn out to be real.

For example, anyone who thinks that insects are unimportant and ineffectual in the grand scheme of things is seriously in error. They have been around a very long time indeed with the oldest fossil record dating back 350 million years, where as we humans by comparison climbed out of the trees just ten thousand years ago. In all that time they have diversified into a multitude of species. Scientists have only managed to name about 1.5 million but believe a further ten to thirty million still await discovery (and this doesn't take into account spiders and mites).

One in four living things on this planet is a beetle. That's more than all the mammals, fish, birds and even plants put together. For every person alive today there is an estimated 200 million insects, or put another way, 300 pounds of little legs, wings and bodies for every pound of human flesh.

Right now, as you read this, an estimated ten quintillion (10,000,000,000,000,000,000) insects (and an equal amount of arachnids) are creeping, crawling, flying and scampering across, above and under the earth's surface. It's a humbling realization that it is invertebrates, not we, who rule the world.

And Costa Rica has a larger share of those creepy crawly critters than most other countries combined. Here you will find more varieties in just one national park than can be encountered throughout the whole of North America and Europe. They range is size from beetles as big as tennis balls to the tiniest fly - a dust mote that could fit onto a pin head with room for twenty more.

Dragonflies and hawk moths speed around at velocities exceeding 35mph, while the lazy giant tarantula will dig a hole in the ground and never come out again. Some butterfly species will die in a day while a queen termite, by contrast, can live to be fifty years old (some even believe she can reach her 100th birthday).

The heavyweight champions of the insect world are, of course, the ants, lifting and carrying over 50 times their own bodyweight (ever tried picking up a school bus?), whilst the bees are the marathon runners, flying sixty miles in a single day to collect pollen for honey production.

A flea can jump 150 times its own length (that's like an Olympic long jumper making a leap of almost quarter of a mile) and a cicada makes a mating cry so loud that we can hear them half a mile away. Jumping spiders see the world through shining eyes with crystal clarity but subterranean army ants are blind and have no eyes at all; yet they still manage to pursue and catch fleet-footed prey using scent organs located on their feet.
We have all heard how a humming bird will flap its wings sixty times in a blink of an eye. Well, that's nothing compared to the ever present blood-sucking midge, who can beat his 1,046 times per second. The list can go on and on and on..

Leafcutter ants tend subterranean gardens of fungus, their only source of food. Lightning bugs mix volatile chemicals within their bodies that light up at night to attract a mate. Tricksy predatory beetles mimic these signals to lure unsuspecting amorous males to their death. The mantis eats her husband's head, but sometimes the roles are reversed and he eats hers, but she still manages to find a place to lay her eggs (most insects have more than one brain, and they are not always located where you would expect). There are caterpillars that resemble bird poo so that they won't be eaten, bizarre grasshoppers that mimic dead leaves and bugs that produce such a volatile stink when molested that your eyes will water. Sphingid moths are armed with spines on their rear legs so that bats attacking from behind will be jabbed in the eyeballs, butterflies have big fake eyes to scare away birds while some cocoons look exactly like very venomous snakes.
And on and on and on.

Despite all these incredible facts, most people's initial reaction to insects is fear. We were brought up with tales of locust plagues stripping crops, poisonous bites and stings, disease and pestilence; to some extent, the stories can be true. Indeed there are biters and stingers, while mosquitoes kill thousands across the globe by transmitting malaria. But these are just a tiny minority, a fractional percentage and not true representatives of the harmless majority. It is this unreasonable fear that makes us spasm whenever a flying bug comes near us, and in the case of wasps, a sudden convulsive fit accompanied by flailing arms and legs can startle them so much that they feel obliged to defend themselves with a quick sting to the back of the neck. We have also been conditioned by advertising to reach for the bug spray whenever our house is invaded, but the truth of the matter is, that in the western world at least, many more people are accidentally killed through inhalation and ingestion of household pesticides than are harmed by the insects themselves.

Some invertebrates are crop pests, causing millions of dollars worth of damage that can lead to starvation amongst rural people, but here in Costa Rica, some farmers and commercial growers have come up with a sensible solution that does not involve using dangerous (and expensive) chemical sprays. With fully one third of all insects, and all spiders, being carnivorous hunters, there is always someone out to eat someone else. Within the towering forests insects can be found in staggering numbers and diversity, including the predators, and so those farmers who have not cleared all the native vegetation away find that they have far fewer problems with pests. The wasps, spiders, ants and assassin bugs leave the bordering forests in search of prey, and like a cloud of death they patrol the crops, consuming harmful caterpillars and beetle larvae. Without invertebrates we would likely not survive. Who would pollinate our plants, fertilize the soil and recycle our waste?

All of us who visit Costa Rica and have at least one national park on the itinerary live in hope of a jaguar sighting. We won't see it though, that's for sure unless you are supremely lucky. We may, if we are fortunate, see monkeys, toucans, and parrots, perhaps even an anteater or a sloth but without a shadow of doubt, we will see insects - money-back guarantee! And if you take an interest in them you will never have cause to finish a hike disappointed.

The Blue Morpho butterfly is no doubt that most beautiful of all Costa Rican insects, but it never keeps still long enough to really get a good look at it. Instead, why not try getting down on your hands and knees and get a closer look at what is going on amongst the leaf litter. You will find hundreds of little critters munching away on plants, hunting each other, communicating and socializing and doing all manner of weird and wonderful things. Take your binoculars and turn them around the wrong way. By looking down the large end of the lens and holding the viewing cup up close you will find that you have become the proud owner of an incredibly powerful portable microscope. Details will be revealed that you could never appreciate before because they were just too small to see.

So be it the frantic mass genocide of an army ant raid, a cute-faced jumping spider bringing down a fly as a tiger brings down an antelope, a hairy caterpillar fending off a wasp with a coat of protective spines, or a swarm of beautiful heliconia butterflies gathered around a passion vine flower, take the time to take a closer look, and as happened to me, a new world will open up before your eyes - and you never know, you may just get over your size hang-up as part of the deal.