Date: 2/23/26 5:20 am From: Cindy McCormack via Inland-nw-birders <inland-nw-birders...> Subject: Re: [inland-NW-birders] Red Crossbill
Hi everyone! This is an excellent question and observation! They are fascinating to see up close.
See the paper on exactly this question:
Benkman, C. W. (1996). Are the ratios of bill crossing morphs in crossbills the result of frequency-dependent selection? Evolutionary Ecology 10:119-126.
> From: Catherine Temple <ctemple99...> > To: Inland NW birders <Inland-nw-birders...> > Cc: > Bcc: > Date: Sun, 22 Feb 2026 10:41:43 -0800 > Subject: [inland-NW-birders] Crossbills > Yesterday I saw a pair of red crossbills gathering grit in the road so I > took some lovely photos of them. Later I noticed that each birds bill (a > male and female) curved in a different direction. I know a lot has been > said about the difference in bill size and the different "types" based on > the types of cones they eat. But if the birds are the same species or type > shouldn't the bills curve in the same direction? Or is it common to have > left and right curved bills within the same type? Or is this a difference > between male and female? I'm really curious as this is the first time I've > been able to get close enough to see the differences. I've attached a photo > of the pair. Thanks in advance if you can enlighten me. > Catherine > > > -- > > *Catherine Temple* > > *Pet Portrait and Wildlife Artist* > > *Clarkston, WA.(208) 791-7052* > <ctemple99...> > > www.catherinetemple.com > www.flickr.com/photos/ctemple/ > > > > > ---------- Forwarded message ---------- > From: Tina wynecoop <wynecoop...> > To: Inland NW birders <Inland-nw-birders...>, Catherine > Temple <ctemple99...> > Cc: > Bcc: > Date: Mon, 23 Feb 2026 01:38:02 +0000 > Subject: Re: [inland-NW-birders] Crossbills > Good question. I've been asking the same question for years. A > well-respected local birder told me I asked the dumbest question. I know > that is not a usual response - but I stopped asking it. Glad you have! > Can't wait for the responses you receive. > Tina > > > > ')> > > > > * > > ________________________________ > From: Inland-nw-birders <inland-nw-birders-bounces...> on > behalf of Catherine Temple via Inland-nw-birders < > <inland-nw-birders...> > Sent: Sunday, February 22, 2026 10:41 AM > To: Inland NW birders <Inland-nw-birders...> > Subject: [inland-NW-birders] Crossbills > > Yesterday I saw a pair of red crossbills gathering grit in the road so I > took some lovely photos of them. Later I noticed that each birds bill (a > male and female) curved in a different direction. I know a lot has been > said about the difference in bill size and the different "types" based on > the types of cones they eat. But if the birds are the same species or type > shouldn't the bills curve in the same direction? Or is it common to have > left and right curved bills within the same type? Or is this a difference > between male and female? I'm really curious as this is the first time I've > been able to get close enough to see the differences. I've attached a photo > of the pair. Thanks in advance if you can enlighten me. > Catherine > > > -- > > *Catherine Temple* > > *Pet Portrait and Wildlife Artist* > > *Clarkston, WA.(208) 791-7052* > <ctemple99...> > > > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.catherinetemple.com%2F&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C639073826398138634%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=RN%2BZ0eL60RFGKU3xXUHxk9dQnu8vUu6qRrfu8DarXyk%3D&reserved=0 > <http://www.catherinetemple.com/> > > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.flickr.com%2Fphotos%2Fctemple%2F&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C639073826398164547%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=gaDcKvsUKj6%2Br%2BfAcqvM%2FezhjCqVZRv0g6pnBrea1vs%3D&reserved=0 > <http://www.flickr.com/photos/ctemple/> > _______________________________________________ > Inland-nw-birders mailing list > send email to: <Inland-nw-birders...> > manage subscription: > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmailmanlists.us%2Fmailman%2Flistinfo%2Finland-nw-birders&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C639073826398185528%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=8T0gKDnC0tbXAkE0W%2Bx%2BC737JrL8kH6Cuqpc38hSdXo%3D&reserved=0 > <https://mailmanlists.us/mailman/listinfo/inland-nw-birders> > > > > > ---------- Forwarded message ---------- > From: <beaharrison...> > To: "'Tina wynecoop'" <wynecoop...>, "'Inland NW birders'" < > <Inland-nw-birders...>, "'Catherine Temple'" < > <ctemple99...> > Cc: > Bcc: > Date: Sun, 22 Feb 2026 18:39:26 -0800 > Subject: Re: [inland-NW-birders] Crossbills > I think that there will be some natural variation in them, just like in any > species. Sometimes violets are white instead of violet for example. This > is what drives evolution. If the bill works better crossed the other way, > then that bird may be able to produce more young and the trait will pass to > the next generation. > > Bea > Bea Harrison > 830-313-0610 > > -----Original Message----- > From: Inland-nw-birders <inland-nw-birders-bounces...> On > Behalf Of Tina wynecoop via Inland-nw-birders > Sent: Sunday, February 22, 2026 5:38 PM > To: Inland NW birders <Inland-nw-birders...>; Catherine > Temple > <ctemple99...> > Subject: Re: [inland-NW-birders] Crossbills > > Good question. I've been asking the same question for years. A > well-respected local birder told me I asked the dumbest question. I know > that is not a usual response - but I stopped asking it. Glad you have! > Can't wait for the responses you receive. > Tina > > > > ')> > > > > * > > ________________________________ > From: Inland-nw-birders <inland-nw-birders-bounces...> on > behalf of Catherine Temple via Inland-nw-birders > <inland-nw-birders...> > Sent: Sunday, February 22, 2026 10:41 AM > To: Inland NW birders <Inland-nw-birders...> > Subject: [inland-NW-birders] Crossbills > > Yesterday I saw a pair of red crossbills gathering grit in the road so I > took some lovely photos of them. Later I noticed that each birds bill (a > male and female) curved in a different direction. I know a lot has been > said > about the difference in bill size and the different "types" based on the > types of cones they eat. But if the birds are the same species or type > shouldn't the bills curve in the same direction? Or is it common to have > left and right curved bills within the same type? Or is this a difference > between male and female? I'm really curious as this is the first time I've > been able to get close enough to see the differences. I've attached a photo > of the pair. Thanks in advance if you can enlighten me. > Catherine > > > -- > > *Catherine Temple* > > *Pet Portrait and Wildlife Artist* > > *Clarkston, WA.(208) 791-7052* > <ctemple99...> > > > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.catherin > > etemple.com%2F&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680%7C84df9e7f > > e9f640afb435aaaaaaaaaaaa%7C1%7C0%7C639073826398138634%7CUnknown%7CTWFpbGZsb3 > <https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.catherinetemple.com%2F&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C639073826398138634%7CUnknown%7CTWFpbGZsb3> > > d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbC > > IsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=RN%2BZ0eL60RFGKU3xXUHxk9dQnu8vUu6qRrfu > 8DarXyk%3D&reserved=0<http://www.catherinetemple.com/> > > https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.flickr.c > > om%2Fphotos%2Fctemple%2F&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680% > > 7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C639073826398164547%7CUnknown%7C > <https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.flickr.com%2Fphotos%2Fctemple%2F&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C639073826398164547%7CUnknown%7C> > > TWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFO > > IjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=gaDcKvsUKj6%2Br%2BfAcqvM%2Fe > zhjCqVZRv0g6pnBrea1vs%3D&reserved=0<http://www.flickr.com/photos/ctemple/> > _______________________________________________ > Inland-nw-birders mailing list > send email to: <Inland-nw-birders...> manage subscription: > > https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmailmanlist > > s.us%2Fmailman%2Flistinfo%2Finland-nw-birders&data=05%7C02%7C%7C6d9a9d499bb4 > > 4a0bf06908de72425680%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C6390738263 > <https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmailmanlists.us%2Fmailman%2Flistinfo%2Finland-nw-birders&data=05%7C02%7C%7C6d9a9d499bb44a0bf06908de72425680%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C6390738263> > > 98185528%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCI > > sIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=8T0gKDn > C0tbXAkE0W%2Bx%2BC737JrL8kH6Cuqpc38hSdXo%3D&reserved=0< > https://mailmanlists. > us/mailman/listinfo/inland-nw-birders> > _______________________________________________ > Inland-nw-birders mailing list > send email to: <Inland-nw-birders...> manage subscription: > https://mailmanlists.us/mailman/listinfo/inland-nw-birders > > > > > > ---------- Forwarded message ---------- > From: Lindell Haggin <lindell4118...> > To: Bea Harrison <beaharrison...> > Cc: Tina and Judge Wynecoop <wynecoop...>, Inland NW birders < > <Inland-nw-birders...>, Catherine Temple <ctemple99...> > Bcc: > Date: Sun, 22 Feb 2026 21:29:40 -0800 > Subject: Re: [inland-NW-birders] Crossbills > I think I’ve read that left over right and right over left are in the same > ration as left-handedness. > > Lindell > > > On Feb 22, 2026, at 6:39 PM, beaharrison--- via Inland-nw-birders < > <inland-nw-birders...> wrote: > > > > I think that there will be some natural variation in them, just like in > any > > species. Sometimes violets are white instead of violet for example. > This > > is what drives evolution. If the bill works better crossed the other > way, > > then that bird may be able to produce more young and the trait will pass > to > > the next generation. > > > > Bea > > Bea Harrison > > 830-313-0610 > > > > -----Original Message----- > > From: Inland-nw-birders <inland-nw-birders-bounces...> On > > Behalf Of Tina wynecoop via Inland-nw-birders > > Sent: Sunday, February 22, 2026 5:38 PM > > To: Inland NW birders <Inland-nw-birders...>; Catherine > Temple > > <ctemple99...> > > Subject: Re: [inland-NW-birders] Crossbills > > > > Good question. I've been asking the same question for years. A > > well-respected local birder told me I asked the dumbest question. I > know > > that is not a usual response - but I stopped asking it. Glad you have! > > Can't wait for the responses you receive. > > Tina > > > > > > > > ')> > > > > > > > > * > > > > ________________________________ > > From: Inland-nw-birders <inland-nw-birders-bounces...> on > > behalf of Catherine Temple via Inland-nw-birders > > <inland-nw-birders...> > > Sent: Sunday, February 22, 2026 10:41 AM > > To: Inland NW birders <Inland-nw-birders...> > > Subject: [inland-NW-birders] Crossbills > > > > Yesterday I saw a pair of red crossbills gathering grit in the road so I > > took some lovely photos of them. Later I noticed that each birds bill (a > > male and female) curved in a different direction. I know a lot has been > said > > about the difference in bill size and the different "types" based on the > > types of cones they eat. But if the birds are the same species or type > > shouldn't the bills curve in the same direction? Or is it common to have > > left and right curved bills within the same type? Or is this a difference > > between male and female? I'm really curious as this is the first time > I've > > been able to get close enough to see the differences. I've attached a > photo > > of the pair. Thanks in advance if you can enlighten me. > > Catherine > _______________________________________________ Inland-nw-birders mailing list send email to: <Inland-nw-birders...> manage subscription: https://mailmanlists.us/mailman/listinfo/inland-nw-birders
