This article is from
Creation 5(1):11, June 1982

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Design in Australian plants—The Australian Greenhood Orchid

wikipedia.commons, Trex21 Pterostylis-Greenhood-orchid

It’s small and lives inconspicuously among the grasses of swamplands and is pollinated by gnats.

Although the flowers are a dull non-eyecatching green, the engineering constructions by which it achieves its primary purpose of pollination are extremely impressive.

The flower is a homemaker’s delight. It has a welcome mat, a front door, a roof, some steps to the kitchen, an insect-proof exit and protective screen. All insects which enter it receive a compulsory tour in exchange for their services as they pollinate the flower.

As a gnat lands safely on the front mat of the Australian Bearded Greenhood Orchid (Pterostylis sp.), attracted by the delights of its nectar, its trip up the large hanging petal is assisted by a ladder (or bearded labellum). Once through the open door formed by the hood or roof of petals, it’s a short trip to the inside base of the flower to sip the ambrosian delights of the nectar.

However, the price for a quick sip is swiftly charged. As soon as the gnat is inside the hood, the ‘spring-loaded’ petal up which it walked, snaps shut! The guest is now a trapped prisoner. There is only one way out for the gnat—up the hallway and through the exit. This hallway is formed by the overlapping and now shut petals. As it moves towards the exit, it must now push past the pollen which sticks to the insect.

Now it can easily push its way up through the grid of fine hairs around the exit to fly away to freedom. However, if it attempts to fly back through the hole for a parting drink, it soon finds that the exit has “disappeared”, hidden beneath the overlapping petals. Even if it could get inside it would find that the fine hairs could no longer be pushed easily out of the way. The inspection of the flower house is a ‘one way trip’ only!

Free to fly away, the gnat finds itself covered with sticky pollen. No, it does not wait around the same orchid, for the flower stays shut for up to thirty minutes—long enough to test the patience of even the most long-suffering gnat. The Greenhood Orchid will never get its own pollen back. The gnat must visit another Greenhood and then proper cross-pollination will have been achieved. Just in case something goes wrong with that particular gnat, the Greenhood resets its spring-loaded petal after a time and all is ready for the next one way trip.

Such intricate pollination devices in orchids were no accident but instead indicate design.

Helpful Resources

By Design
by Dr Jonathan Sarfati
US $15.00

Readers’ comments

B. H.
I have grown (and photographed in the wild) quite a number of these exquisite creations, including the Pterostylis curta pictured in your article. My favourite Australian native orchid is Caleana major, the "Flying Duck Orchid." Its small flowers bear an uncanny resemblance to a duck, the head of which, like the Pterostylis in the article, is also on a trigger mechanism.

I've also grown a number of Sarracenia species (insectivorous pitcher plants) in the past. The flowers of Sarracenias are also cleverly designed so as to make self pollination by insects difficult.

The entrance to the flowers require the insect to pass by the stigma where it deposits pollen from a previously visited flower. Then it picks up pollen inside the bloom before having to push past one of the flower's petals to exit (thus avoiding the flowers own stigmas on the way out and preventing self-pollination).

There are countless other similar examples of brilliant design from the master creator.

Romans 1:20 (KJV)
michael S.

The standard evolutionary response would be: "they evolved together, a symbiotic relationship beneficial to both species".

Which is, as a hypothetic, pretty fortuitous in that this fits with their evolution-tale but doesn't by any means prove any evolution actually occurred.

I know this from debating evolutionists. It's a standard response from them but the problem is that it is just a hypothetical assertion.

As far as I know, this standard response is the response for all such examples, I don't know of any evolutionists that have ever actually tried to explain how a specific design such as this, would or did come about via evolution. Therefore it seems unreasonable to see their response as plausible given there is no empirical data to support such an evolution having happened. With no histories to their "evolution" it's a matter of choice, you believe the obvious and true answer, a designer, or you don't, and you ignore the scientific facts of such design.
R. L.
A few disjointed thoughts.
I think you article is describing the Pterostylis sensu stricto group and not a Bearded Greenhood; this would have been equally true in 1982 when the article was written as well as today.
Pterostylis sensu lato is a very broad genus and by 2006 had been divided into several genera (10 are known in South Australia). Today the Bearded Greenhood is now a separate genus.
The picture featured is Pterostylis curta, common name Blunt or Curt Greenhood, of which its habitat is the damper conditions of forest, coastal dunes and shady gullies. Pollinators appear to be both midges and fungus gnats. It is not certain what attracts the pollinators to P curta.
Pterostylis sensu stricto is the most widespread of the greenhoods. They occur from the littoral zone to the alpine regions, avoiding deserts, often found in forest, swamps, heath plus riparian zones.
Concerning the Bearded Greenhoods, Plumatichilos (previously included in Pterostylis genus); little is known about its pollination. It would appear that the event has not been described, possibly not even observed, although fat bodied flies have been observed around the flowers. Its habitat is quite varied from swamp margins to rock outcrops.
I find orchids speak to me of God’s creativeness. The descriptive common names demonstrate this – spider, daddy-longlegs, helmets, greenhoods, bearded, parson-bands, onion, leek, donkey, bulldog, leopard, pink fingers, flying duck, green frog, hyacinth, potato, ladies tresses, etc.
I strongly suspect though that variety of our species is due to genetic loss.
I appreciate the work that CMI does and the standard that is set but as webmaster for (Native Orchid Society of SA) I think the article needs a little adjustment.
David Catchpoole
Thank you for your submission. As this article is an 'archive' record of what was originally published in Creation magazine, we will let your comment provide readers with the necessary update. We very much appreciate you sending it to us.
Bruce A.
ANOTHER STUNNING article which strengthens one's faith and trust in our Almighty God ....Please keep it up !
Joan C.
Very informative. It coud only be our marvellous designer. Random no way. (evolution)

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