Genetic advantage of single over pea comb

[Tired old Rooster]

Anecdotal here. I only see single comb birds here, even the mutts. Gets to sub zero in winter but not crazy cold like northern US or Canada. Summer here is like if hell had a sauna. I think the single is naturally superior.

 

[Red Mangrove]

View attachment 3605656View attachment 3605653

Straight and pea comb rooster comparison. Similar housing for both birds (wire coop with tarp top, wooden roosting branch, about the same height off the ground.

Thank you for these images. There's obviously greater surface area and heat discharge in the single comb, but does it actually impact function at all? I've seen zero issues in Florida with Cubalaya, Ameraucana and Brahma pea combs

 

[Florida Bullfrog]

Thank you for these images. There's obviously greater surface area and heat discharge in the single comb, but does it actually impact function at all? I've seen zero issues in Florida with Cubalaya, Ameraucana and Brahma pea combs

I can’t see where the heat exchange aspect could mean much, unless roosters have some different need for heat regulation that a hen does not. As straight combed hens generally won’t come close to matching a rooster comb’s surface area, and where in nature RJF hens have hardly a comb at all.

And yet, nature seems to select for a straight comb when chickens are left to their own devices. I’ve referenced an informal experiment in other threads that a biologist named Brisbin did where he allowed bantams of all manner of domestic breeds intermix free range in a farm yard setting, allowed nature to select the survivors for several years, then turned them loose in Georgia river bottom woods and left them feral in the woods for a few years more. The end result was basically a black junglefowl with a straight comb.

Is there a direct survival advantage to straight combs, at least in the tropics and subtropics? Is is purely sexual selection by hens?

 

[Tired old Rooster]

I can’t see where the heat exchange aspect could mean much, unless roosters have some different need for heat regulation that a hen does not. As straight combed hens generally won’t come close to matching a rooster comb’s surface area, and where in nature RJF hens have hardly a comb at all.

And yet, nature seems to select for a straight comb when chickens are left to their own devices. I’ve referenced an informal experiment in other threads that a biologist named Brisbin did where he allowed bantams of all manner of domestic breeds intermix free range in a farm yard setting, allowed nature to select the survivors for several years, then turned them loose in Georgia river bottom woods and left them feral in the woods for a few years more. The end result was basically a black junglefowl with a straight comb.

Is there a direct survival advantage to straight combs, at least in the tropics and subtropics? Is is purely sexual selection by hens?

A roo tends to be way bigger than a hen, so more need to dissipate heat.
Also, running around looking like you are wearing a fire truck for a hat lets the ladies notice you more.

 

[JacinLarkwell]

Is there a direct survival advantage to straight combs, at least in the tropics and subtropics? Is is purely sexual selection by hens

I know with other species of animals, female selection doesn't always go for a evolutionary success. There was a fly species that had eye stalks and the females selected males with longer stalks, but those were not genetically superior males. And last I read, female lions preferred males with black in their manes, when (I can't remember the reason in the reading) those males weren't the ones that 'should' be the favored male looks

 

[DarJones]

"Laying eggs in winter in a cold climate doesn't sound like an evolutionary advantage to me"

Humans shaped chicken evolution for roughly the last 3500 years. We provided selection pressure to lay eggs in quantities well beyond what jungle fowl lay. We wanted chickens to lay in cold climates. We selected for traits that produce eggs even in winter. Evolutionary advantage? You betcha, we killed em if they did not lay eggs in winter!

 

[RobG7aChattTN]

Single comb is an advantage in hot climates. Light body size is also an advantage. Light colored feathers are another heat advantage.

What about cold climate advantages? Pea comb, rose comb, cushion comb, and flat comb are all advantaged to different degrees in cold climates. But it takes a lot more to make a cold weather adapted chicken. Large body size, thick fluffy feathers, and yellow legs are all advantages in cold climates. How so? Large body size and thick fluffy feathers are better for generating and retaining heat. Yellow legs are from sequestering caroteinoids. Guess what a chicken needs to lay eggs? Yes, carotene! Where does carotene come from? It comes from grass and plants chickens eat. In a cold climate, there is a shortage of green plants in winter. Yellow leg chickens have a small but significant advantage. Also, midden heaps prove all chickens from 2000 years ago had white legs. As they moved further from the equator, yellow legs became more and more common. We know yellow legs came from green junglefowl along with several other traits needed in cold climates.

Yellow legs came from Grey Jungle Fowl. Green Jungle Fowl are by far the least cold tolerant/most tropical of the Jungle Fowl.

 

[RobG7aChattTN]

I can’t see where the heat exchange aspect could mean much, unless roosters have some different need for heat regulation that a hen does not. As straight combed hens generally won’t come close to matching a rooster comb’s surface area, and where in nature RJF hens have hardly a comb at all.

And yet, nature seems to select for a straight comb when chickens are left to their own devices. I’ve referenced an informal experiment in other threads that a biologist named Brisbin did where he allowed bantams of all manner of domestic breeds intermix free range in a farm yard setting, allowed nature to select the survivors for several years, then turned them loose in Georgia river bottom woods and left them feral in the woods for a few years more. The end result was basically a black junglefowl with a straight comb.

Is there a direct survival advantage to straight combs, at least in the tropics and subtropics? Is is purely sexual selection by hens?

One thing about the straight comb is it displays to the female the health, vigor and testosterone of the male. Inna straight-comb flock the alpha male will have the biggest, reddest comb. If he gets injured his comb will get smaller and be less red and the next rooster in line becomes the alpha and his comb will get bigger and more red. They did an experiment with attaching fake combs on roosters and the hens would pick the males with the biggest, reddest combs. Not sure what would happen if a pea comb bird that was far superior in every other way was introduced.

 

[fluffycrow]

28°C today. The highest temperature I've not seen my pea combed birds panting

 

[fluffycrow]

One thing about the straight comb is it displays to the female the health, vigor and testosterone of the male. Inna straight-comb flock the alpha male will have the biggest, reddest comb. If he gets injured his comb will get smaller and be less red and the next rooster in line becomes the alpha and his comb will get bigger and more red. They did an experiment with attaching fake combs on roosters and the hens would pick the males with the biggest, reddest combs. Not sure what would happen if a pea comb bird that was far superior in every other way was introduced.

I'd love to read that study, could you link it?