Toucan-Barbet (Semnornis ramphastinus)

Toucan barbet (Semnornis ramphastinus). Creative commons: Wikipedia /Vince Smith.

Toucan-Barbet (Semnornis ramphastinus). Creative commons: Wikipedia /Vince Smith.

Plate-billed Mountain-Toucan, Andigena laminirostris, near our Dracula Reserve. Photo: Lou Jost/EcoMinga.

Plate-billed Mountain-Toucan, Andigena laminirostris, near our Dracula Reserve. Photo: Lou Jost/EcoMinga.

One more quick post about birds before returning to my talk about endemic plants. While our group of botanists and ornithologists were visiting our Dracula Reserve, we saw and heard the Plate-billed Mountain-Toucan (Andigena laminirostris, subject of my last post) but we also often heard the remarkable Toucan-Barbet (Semnornis ramphastinus). Curiously, these two birds have a remarkably similar and rather bizarre color pattern. Both have black crowns, blue throats, ochre backs, light yellow rump patches, red lower underparts (though the red is more extensive in the barbet), and bright warm yellow flank patches under the wings. I think this is unlikely to be an accident, and may be a case of mimicry on the part of the barbet. Perhaps the mountain-toucan, which eats nestlings and has a nasty beak, is feared by other birds? And so maybe other birds shy away from the barbet too, reducing competition for fruit when a barbet arrives in a tree? Speculation, I know, but what the heck–this is a blog, not a textbook.

Maybe this resemblance may also help the barbet win fights over nest cavities, if they rob cavities from other birds.

I should note that the Toucan-Barbet and the mountain-toucan belong to different families, though the families are sister groups. Most other members of both families don’t look like this, so the similarity of these two species is probably not due to inheritance from a common ancestor.

Later today I will add another post about mimicry of plumage colors and patterns in birds, inspired by a comment by Bruce Lyon on Jerry Coyne’s website which discusses my mountain-toucan post.

Toucan barbet (Semnornis ramphastinus). Painting by Lou Jost.

Toucan-Barbet (Semnornis ramphastinus). Painting by Lou Jost.

Lou Jost
http://www.loujost.com

4 thoughts on “Toucan-Barbet (Semnornis ramphastinus)

  1. Pingback: Interspecific plumage mimicry in toucans and New World barbets | Fundacion EcoMinga

  2. Pingback: Plate-billed Mountain-Toucan, Andigena laminirostris | Fundacion EcoMinga

    • Thanks for the question, Peter. One way would be to experimentally change the Toucan-Barbet’s colors with dyes to ruin the mimicry, and see if other birds behaved less fearfully around the dyed birds (or, alternatively, that Plate-billed Mountain-Toucans acted more aggressively towards the dyed birds). Or, find places with the Toucan-Barbet but not the Plate-billed Mountain-Toucan, and see if other birds there were less afraid of the Toucan-Barbet.

      If one doubts that mimicry is likely between two birds, see my next post:
      https://ecomingafoundation.wordpress.com/2015/07/24/interspecific-plumage-mimicry-in-toucans-and-new-world-barbets/
      Even in the cases discussed there, it remains possible that some other factor is causing both species to converge on the same color pattern. But it seems unlikely that some regional factor would be able to produce such exact similarity between species.Tests similar to those I mentioned above could be applied to these species to prove mimicry.

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