Thanks for your observations! I’m especially interested in hearing about your growing the orchid, because I’ve not been able to keep one around long enough to see what you’ve seen.

Good for you for deciding to revise what you teach your students. You’re right – it’s the kind of thing we’d all LIKE to be true!

Mary

Regarding the resemblance, or lack thereof, of the orchid to the lantana and milkweed….

I have grown this orchid, and I must say that the resemblance of the inflorescences of this orchid to the inflorescences of the milkweed and lantana is striking. The orchids even change color as they mature similar to what the lantanas do, with the oldest ones being darker, and the younger ones having more yellowish-orange lips. And the presentation of these flowers (orientation, and shape of the inflorescence), on my plant anyway, really gave the same look, from a moderate distance, as the inflorescences of the other two plants. To my eye, the similarity in appearance between the lantana and milkweed seems no greater than the similarity of the orchid to either of these two plants.

This all being said, it is sad that the experimental evidence does not seem to give support to this mimicry idea. It is such a lovely story – a story you really WANT to be true! I’m going to have to revise what I tell my students about these plants.

Well, flower shape can be important. Darwin showed that in orchids early on (http://tinyurl.com/228lfa). Further, long, tubular flowers have pollinators that can reach down that tube, and other shapes have been shown to prevent all but certain pollinators from having access to nectar (http://tinyurl.com/2adlxc).

However, I would agree that pollinators are no doubt attracted to cues that we can’t even begin to imagine. I’ve only seen studies of visual cues and odor cues, but I’m far from familiar with the body of pollination literature.

As far as most pollinators being generalists, I certainly don’t know about that. Here’s a quote from the first link I cited in this comment (it’s specifically about tropical plants, and that might make a difference): “In the tropics there is diversity of flower color, smell, shape, and size, each combination of characteristics being attractive to specific pollinators. This kind of specialization that results from a high degree of competition between species causes high species diversity (Kricher 1997). If a plant were visited by a generalist species, one which visits a variety of species, the plant would have little chance for its pollen to land on another member of its species. ”

Thanks for making your interesting points.

For example, I wouldn’t be that surprised if flower shape does not hold a significant attractivity, because many flowers are attacked by herbivores and thus aren’t really presenting as perfectly shaped, but they are still pollinated most of the time… Colours may be another issue, but it’s harder to know what pollinators do really see (it’s not been studied in many insect species apart from domestic bee).

You’re right about the Epidendrum – clicking on the images will give larger views, and the difference is even more obvious in those images.

The Roy and Widmer paper includes pictures of three other sets of floral mimics, all of which look more similar (within sets) than the Epidendrum does to the Asclepias and Lantana. The Asclepias and Lantana are examples of Müllerian mimicry, though. I wonder if it’s harder to find floral examples of Batesian mimicry. If you remember the gladiolus species, btw, do please post it. Inquiring minds….

(Awesome post, by the way. You should do more of it!)

Good example – those snakes. They’re analogous to the Viceroy/Monarch butterfly mimicry, and I’ve seen reference to their similarity in the scientific literature as well. Thanks for pointing them out.

I like the idea of mythbusters undertaking floral mimicry! Cool.

that seems to be another case for the “mythbusters” team at Discovery…..uuummmh!.

thanks miconia for your excellent and fun presentation.

olmedo

I think scientists are just like everyone else in that regard. As Paulette Bierzychudek said, “Myths die hard.”