This is the first textbook I've read since college, which has been well over a decade. This subject was far from my major (Computer Science) but I'd say this book provides a very thorough understanding of the subject with tons of examples to illustrate both how behavior works and adapts.
I find this subject fascinating because conceding that all animals (including us) are essentially cleverly-crafted machines, I'm curious how they work. Alcock warns that there's not genes "for" a specific behavior, genes code for proteins and genes are turned on or off by environmental conditions that can exist both in and outside of the body. But I came away certainly thinking genes do determine behavior to a large extent, depending on how you think about it.
There's a few examples given throughout of a single gene which modifies a particular behavior. A single gene in fruit fly larvas make them either sit in one spot, or rove about. A single gene in mice affects hippocampus development which underlies the differences in spatial memory performance. Knocking out the fosB gene in mice makes them indifferent to their young. A single mutation in the per-gene will drastically throw off an animal's circadian rhythm. It seems to me that in some cases we're getting dangerously close to being able to ascribe behaviors to particular genes. Again, Alcock would say genes code for proteins and enzymes, which make hormones which develop certain neuron pathways and structures.
There's some fascinating stories here...
--Mice engage in infanticide for three weeks after ejaculation during copulation, but after three weeks have passed their own offspring are born and they grow parental for a time. Then seven weeks after ejaculation have passed they return to infanticidal behavior. This seems to be an adaptation to destroy rival offspring during the three weeks of pregnancy, and by the time seven weeks have passed their own young will have dispersed and the infanticidal behavior can resume. Scientists have found that by "speeding up" the number of days the mice think have passed using artificial lighting, they could cause the mice to attack young or not, showing that it is based to some extent on an internal clock, and corroborated by environmental cues about time passage.
--Developmental homeostasis is the ability for an animal to acquire proximate foundations for correct behaviors, even under bad conditions. In one case researchers re-routed the optical nerve in an infant ferret to the auditory cortex of the brain, and it actually developed as a second visual cortex. The genes in the cells responded to the visual messages and developed along that pathway. Weird!
--Fixed action patterns are behaviors elicited automatically by a cue. Some species have learned to exploit this in others. The rover beetle uses an attractant pheromone normally used by other ants. This causes ants to accept its larva into their brood chambers, which proceeds to eat the ant eggs. If that isn't enough, this species of beetle also knows how to "tap" ants mandibles to elicit the automatic response of regurgitating liquid food.
--Bird migration is covered a few times throughout the book. The direction they fly in appears to be mostly gene-determinate (although singing interestingly is learned in some species, leading to local "dialects.") But what amazed me was scientists hybridized birds that migrate southwest with birds that migrate southeast -- the hybrids were an intermediate and fly due south! It makes perfect sense, but is still so weird.
--The male prairie vole wanders over a larger area to mate than the female, and thus has a larger hippocampus to map out landmarks. Most interestingly, this part of the brain actually SHRINKS during non-breeding season when it's not used. The testes of most birds shrink during non-breeding seasons as well. It makes sense from an efficiency standpoint.
--The last chapter on the evolution of human behavior is especially well-written, often having some dark implications. Step-children are more often abused, mothers of step-children and adopted children spend less on food. These could be maladaptive by-products of the previously adaptive trait of treating genetic offspring favorably. Infanticide and rape are covered in some detail. Of course Alcock is not trying to justify any of this, just explain why it happens from an evolutionary perspective. But when you have an understanding from previous chapters of the brutality of how nature operates, including things like infanticide and parent-sanctioned siblicide, it's difficult to not come away a bit disturbed.
You really start to question what behaviors you have that are remotely "yours." What does it even mean to be "you?" Those aren't the questions Alcock is trying to elicit, but they inevitably came to my mind because of my philosophical views about the world.
I liked the pervasive cost-benefit analysis that comes up in later chapters. Crows fly to the exact optimal height for dropping and breaking open whelks to eat, not wasting energy flying higher than needed. Some birds are able to regulate the sex of their offspring, depending on the quality of the territory they inhabit. Better territory dictates more females who may stay around to help with the next brood, but for birds living in a poor territory a female is another mouth to feed. There is a cost of exaggerated begging in a brood of baby chicks in that they deprive their siblings of food, and harm the reproductive success of someone they share genes with. So the degree to which individuals moderate their begging behavior is a function of the degree of relatedness among the nestmates. It has been found, as predicted that broods of mixed parentage are louder than broods of monogamous species where the children share more genes.
This gets more complicated when Alcock delves into how altruism appears as a function of helping those related to you. For example, mathematically your genes have more chance of continuing into the future if you sacrifice parenting one child which will have 50% of your genes, for helping a sibling raise three children who each have 25% of your genes.
It gets even more complicated with "eusocial" species which have whole non-reproductive castes who are helpers, foragers, defenders, etc. Species of this type are usually haplodiploid. This is when eggs destined to be males are unfertilized and so the male gets only one set of chromosomes, not two, nothing from the father. In one wasp species this results in relatedness among the daughters of the queen of approximately 75%~. Since their father has only one set of chromosomes the sisters share a full 50% of genes from the father already, and another 0-50% from the mother. Compare this 75% relatedness to humans where you're genetic relation to a sibling is only around 50%. This high degree of relatedness due to haplodiploidy is used to explain eusocial, self-sacrificing behavior in many species. An interesting aside -- these sister wasps share LESS relatedness with their brothers. The brothers get none of the father's genes, so there's 50% of possible commonality missing with their sisters, and they share only between 0-50% of their common mother's genes. As predicted, this means the sisters help feed their brothers less.
Nature starts to look like one big mathematical calculation, but it makes sense.
I read the Seventh Edition of this text, from 2001 and I'm sure some info has changed or been enhanced by new experiments or genome sequencing. The latter was a big factor in the updates to Dawkin's "The Ancestor's Tale" between the first edition in 2004 to the second in 2016. But the focuses of these two books are quite different. Furthermore, most animal behavior is determined by hypotheses, predictions and observation/experimentation and do not require the level of the genome itself.
For example; hypothesis: A resident defends his territory more strongly than a rival will try to take it because he has more to lose than the rival, not only the resources of the territory, but the time put into creating relationships with neighbors which saves them time and energy engaging in struggles. Prediction: The probability a territory holder that is experimentally removed and later released will reclaim his territory is a function of how long the replacement has occupied the site in his place -- this is true. Another hypothesis: Nesting colonies of foraging birds serve as an "information center" and others will follow those who have recently found food. Prediction: If info is shared they will leave together and follow in the same direction -- this is true.
Of course I would love to see what experiments have been done in intervening years to corroborate or refute various theories, or clear up a few questions here and there which are left uncertain. But those new textbooks are so pricey!