{"id":44930,"date":"2017-01-09T06:38:16","date_gmt":"2017-01-09T13:38:16","guid":{"rendered":"http:\/\/www.featheredphotography.com\/blog\/?p=44930"},"modified":"2017-01-09T07:19:44","modified_gmt":"2017-01-09T14:19:44","slug":"owls-and-plumicorns","status":"publish","type":"post","link":"https:\/\/featheredphotography.com\/blog\/2017\/01\/09\/owls-and-plumicorns\/","title":{"rendered":"Owls And Plumicorns"},"content":{"rendered":"

Verifying the actual function(s) of some biological structures has proven to be elusive.\u00a0The presence of plumicorns\u00a0in owls is a case in point.<\/p>\n

Ear tufts in owls are not ears and they have nothing to do with hearing. And they aren’t horns either. The technical term for them is plumicorns (Latin for “feather-horn”). About 50 of the 225 living owl species have plumicorns.<\/p>\n

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\"great-horned-owl-1767b-ron-dudley\"<\/p>\n

1\/400, f\/8, ISO 400, Canon 40D, Canon EF 500mm f\/4L IS USM, not baited, set up or called in<\/em><\/strong><\/p>\n

When we think of plumicorns it’s probably the Great Horned Owl that first comes to mind for most of us. In this species\u00a0plumicorns are\u00a0quite prominent and as we can see here both sexes have them. This is a mated pair and the female is the larger bird on the right.<\/p>\n

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\"great-horned-owl-0223-ron-dudley\"1\/2500, f\/7.1, ISO 250, Canon 7D Mark II, Canon EF 500mm f\/4L IS II USM, not baited, set up or called in<\/strong><\/em><\/p>\n

Usually Great Horned Owl plumicorns are held erect but this bird flattened them against its head for almost the entire time I spent with it. From watching the bird carefully I’m confident that it wasn’t a reaction to my presence but I can’t explain the behavior with any confidence.<\/p>\n

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\"burrowing-owl-6291b-ron-dudley\"<\/p>\n

1\/320, f\/7.1, ISO 640, Canon 7D, Canon EF 500mm f\/4L IS\u00a0USM + 1.4 tc, not baited, set up or called in<\/em><\/strong><\/p>\n

Burrowing Owls are one of the many species of owls without plumicorns.<\/p>\n

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\"short-eared-owl-1473b-ron-dudley\"<\/p>\n

1\/3200, f\/6.3, ISO 800, Canon 7D Mark II, Canon EF 500mm f\/4L IS II USM + 1.4 tc\u00a0not baited, set up or called in<\/em><\/strong><\/p>\n

Short-eared Owls have them but they’re small (thus their common name)\u00a0and usually not held erect so they’re difficult to see. This is one of the relatively few images I have of the species where they’re apparent.<\/p>\n

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But the actual function of plumicorns is yet to be verified. Several hypothesis have been proposed including the following:<\/p>\n