Orchids: Masters of deception

With their pungent aromas and vibrant blooms, orchids lure insects, green thumbs and romantics alike. In this Science Friday story, the curator of orchids at the New York Botanical Garden describes how the plants manipulate insects into pollinating them.

TRANSCRIPT

With their pungent aromas and vibrant blooms, orchids lure insects, green thumbs, and romantics alike.

Up next, the Curator of Orchids at the New York Botanical Garden describes how the plants manipulate insects into pollinating them.

Science Friday has the story.

[ Mid-tempo music plays ] [ Microscope clicking ]

Coming into this room for an insect might be just as overwhelming as it is for our visitors.

There's so much color, pattern, and fragrance in here.

But depending on what type of species you are, you might be drawn to an orchid...

That may have spots, hairs, warts, and even smell really unpleasant.

Or you could gravitate towards...

Something sweet perhaps, looking for a nectar reward.

This sensuous sea of orchids just might cause you to bug out.

They're probably one of the most diverse groups of flowering plants, with over 33,000 naturally occurring species.

Dozens of which are on display at the New York Botanical Garden's annual Orchid Show.

So I have a lot of children under my care.

Marc Hachadourian is the garden's Curator of Orchids, a responsibility that borders on obsession.

Been growing orchids now for over 30 years, so they do have a little bit of control and a little bit of power over me.

But it's something that I'm willing to submit to because I just -- orchids are just such an important part of my life.

Marc isn't alone in his compulsion.

These plants have evolved the incredible ability to convince many species to do their bidding.

Everything we see and appreciate about orchids, in terms of the flowers themselves, the colors, the patterns, are really are there to achieve reproduction.

They are the reproductive organs of plants.

Orchids turn their pollinators into slaves to their desires, drawing them in with unseen forces.

There are orchids that smell like roses, there are orchids that smell like jasmine, and there are many orchids that smell like you should be checking the bottoms of your shoes for something you might have stepped in.

Not particularly alluring to us, but flies love it.

Some orchids will produce chemical fragrances that mimic the pheromones of insects in order to bring the insect to the flower itself.

Others might mimic the aroma of the perfect nursery for a pollinator's larvae.

A group of South American orchids, this particular genus, actually produces some of the same chemical compounds produced by mushrooms.

That you might see a monkey face in the bloom is purely coincidental.

But to its pollinator, it sees a mushroom that it would lay its eggs on for its larvae to survive.

This type of deceptive lure is a hallmark adaptation of the orchid family.

The lip, or labellum, is a specialized petal found on the flower of an orchid.

The lip, or labellum, can be modified into strange colors and patterns to guide a pollinator towards its nectar reward, like a runway for a visiting pollinator.

Or in some extreme cases, the lip, or labellum, can be modified into a completely different shape.

It can resemble even the female of a species of insect, which actually will trick the males into attempting to mate with the flower.

And end up fertilizing the flower instead.

And this level of trickery turns the orchid into a specialist, dependent on its pollinator.

In some cases, it may even be a one-to-one relationship in which there's only one species of insect or animal that pollinates that one species of orchid -- the most famous example being the Darwin star orchid that has this long nectar spur at the back of the flower.

He theorized that, since it was a white flower only fragrant at night and with that long nectar spur, it was pollinated by a long-tongued moth with a 12-inch-long tongue.

Lo and behold, the moth was discovered 42 years after Darwin's prediction.

Special relationships like these hinge on an orchid's ability to transfer their pollen from one plant to another.

To ensure this, orchids have evolved a unique method of distributing their pollen.

The pollen itself on an orchid is not granular or dust-like, but fused into a solid mass.

Known as the pollinium, this shotgun approach to fertilization has obvious benefits.

By concentrating all of your pollen into one solid mass, you don't just get a little bit from flower to flower.

You get an efficient transfer of a lot of genetic material.

And orchids typically need a lot of pollen to fertilize all of their seeds.

A single seed pod of an orchid can have upwards of 250,000 or, in some cases, up to over 1 million seeds in a single seed pod.

You may have seen and enjoyed one of these seed pods in the form of a vanilla bean.

As with most orchid species, these seeds are tiny and actually lack the nutrients to grow on their own.

And why should they when they can get those from another organism?

Orchid seeds require the presence of a specialized group of fungi.

That fungus essentially provides the orchid embryo with the nutrients it needs to grow and develop into a seedling.

Kind of like a parasite, an, oh, so beautiful parasite.

They're just a group of plants that is not only highly evolved, but also highly adaptive might be a better way of looking at it.

True, but that doesn't explain why they cause such an infatuation.

There might be things that we may not realize and that the orchid is drawing us in and sort of attracting us, as well, with something beyond our natural perceptions.

There's no science to back that up, but would it surprise you?