The fascinating and complicated sex lives of white-throated sparrows

I see a scientist using a red band tag first and later in the video a silver-blue one for a different bird. Do they control for tag color when banding birds? https://www.cell.com/current-biology/fulltext/S0960-9822(15)... some birds are known for their color/visual preferences and the measurement could ostensibly be a cause for the results: a confounding variable like in those mice studies where male or female scent inadvertently affected rat behaviour.

Since we are talking bird and mating rituals, HN member once pointed out to me the fascinating bowerbird mating rituals[1] that result in them building fairly ornate structures showcasing their resource gathering skills.

[1]https://blog.nature.org/2021/01/04/bowerbirds-meet-the-bird-...

It seems, to me, a similar dynamic to human pairings (at the edges). The more dominate aggressive females go for the more nurturing males, and vice versa. Then you're left with having pairings of dominate types who fight like 'cats & dogs', and never really know much about the more subdued pairings.

Similar to Love Island ;)

Reminds me of evolutionary stable strategies in game theory. In this case, the payoffs are even for two strategies in repeated games. There are also unstable games like this one: https://blogs.cornell.edu/info2040/2016/11/26/side-blotched-....

Huh this is news to me. My field guides all mention the color variation but don’t mention differing behavior. One guide even incorrectly says its based on age (it is worth noting they do vary in plumage depending on age, but in a different way).

Another bird that is sort of like how they describe in the article is the Ruff. It is a beautiful type of sandpiper where males are split into 3 categories with different appearance and behavior.

Anyone know what types of chicks result from tan-striped/tan-striped couplings? Are they a mixture of white-striped and tan-striped? Or are they all tan-striped? And likewise for white-stripe/white-stripe couplings? The article says the single-striped couplings are rare in nature, but I'm wondering none-the-less.

John James Audubon was a white supremacist and purchased several human beings. I worry that we are in danger of a return to scientific racism with the renewed interest in eugenics.

There's a lot more going on behind those white throats than meets the eye

Two sexes (male, female), each with two variants (white throat, yellow throat), creating four genders (wM, yM, wF, yF).

Males and females need to pair or there will be no new sparrows. However opposite variants also need to pair or for behaviour reasons there will be no successful young.

For instance, wM-wF spend so much energy fighting with each other they fail to raise young.

The y variants are less aggressive but better with young and are the most popular mate choices. The y-variants are also monogomous while the w-variants are not.

The aggressive w-variants grab all the y-variants as partners. The result is that y-y pairs are rarely (never?) seen, even though they could produce young.

The article notes that yellow throats have different food strategies from white throats. This will also tend to reinforce alternate gender pairing.

An MF pair is going to bring in less food if both are going after the same sources (they might start fighting!) while if each has a different strategy the young are less vulnerable to food shortages should one strategy or another not produce at any given time.

The four gender outcome seems to be in a sustainable equilibrium. If one is favoured, say wM-yF, then these sparrows would become like most other birds, with males having one colour pattern and females another.

Instead, behaviours have somehow distributed themselves across genders so a successful couple needs to match both if they are to raise the next generation of young.