How can we be sure that predation is the key selective pressure, rather than one of these other variables?
Why can it not be a mix of both?
7 Matching Annotations
- Jan 2026
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bookshelf.vitalsource.com bookshelf.vitalsource.com
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It may take some time getting to know a particular species before it is possible to ask good questions about its behaviour and ecology. Niko Tinbergen’s work on gulls was the result of many years’ painstaking observations of their behaviour in the wild.
I liked how Tinbergen dedicated a good bit of his life to gulls, and that's the point where you can go ahead and ask, "What's next? How do we proceed? What is this behavior we don't understand?"
Did Tinbergen consider all birds before he chose gulls? Or was it always a fascination for him?
It would be good to add a specific question that Tinbergen asked himself and how he approached it.
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The comparative method involves comparing different species to see whether differences in behaviour or morphology are correlated with differences in ecology.
Has this been done with humans? Comparing humans to a specific different species?
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oestrus
Wasn't aware of what this meant: it means when they are fertile and ready to mate, a point right before ovulation
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Another possibility is that British and Dutch tits use the same cues but in Britain the cues are better predictors of the food supply that will be available to nestlings. In the Hoge Veluwe, over the last three decades there has been little change in early spring temperatures (when the adult tits are forming food reserves to breed) in contrast to the markedly warmer late spring temperatures, which influence the caterpillar food available to nestlings. The adult tits may, therefore, not have been able to predict the earlier food availability for their offspring (Visser et al., 1998).
So, not only do they need similar types of reaction norms, but the Dutch birds also lack better cues for food supply?
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The other possibility is that earlier breeding has simply arisen through phenotypic plasticity, with no need for any genetic change.
What is this specofoc gene that does this? Hod does the environment affect it to alter the phenotypes?
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When the phenotypic variation is continuous, the relationship between phenotype and the environment for each genotype is called a reaction norm
The relationship between how a single gene can change/alter the phenotype depending on its environment, assuming that the variation of the phenotypes is continual
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