Paternal offspring rearing, monogamy and female jealousy

Not knowing more about zoology than anybody else, I’m wondering about the following:

Is there a strong tendency for species where the male takes care of the offspring, either before or after they’re born, to be monogamous? Do monogamous species have a strong tendency for the male to take care of the offspring, either before or after they’re born?

In monogamous species (aside from humans), how does the female tend to react when the male reproduces with other females?

You probably mean “hatched”. Not too much monogamy in the mammalian world.

In emperor penguins the couple takes turns caring for the egg/chick and making eating runs to the sea. If the chick dies including if the egg breaks the relationship is over. If the chick makes it to be on their own the relationship is also over.

The penguins are monogamous only during courtship till they leave the chick.

Yes, in the vast majority of animals who are socially monogamous, the father contributes much more than usual to caring for the mother or offspring. They are definitely related. Socially monogamous can mean pair-bonded for the breeding season, or for a lifetime (or nearly so).

However, pretty much all the species we’ve ever called ‘monogamous’ turned out to be rampant sexual cheaters upon closer observation, and ‘divorce’ and abandonment isn’t uncommon even if those that supposedly ‘mate for life’. That goes for all birds. There are no animals as far as I know that have been proved to be sexually monogamous. This means that fathers in species that pair-bond are fairly often going to be raising the offspring of other males.

‘Monogamous’ animals who cheat seem to be sneaky as hell about it, just like people. They take pains to do it far away from their partners, and cuckolded spouses will react by attacking the rival if they catch them in the act.

It’s both hilarious, and depressing.

Humans are definitely a pair-bonding species with off-the-charts male investment, but we have too large a history of polygamy and promiscuous behavior, socially sanctioned or not, to call ourselves a socially monogamous species, IMO.

And some of the cheating is purely a biological construct. On Nature specials, a female bird will select a mate, mate, sit on the nest, and lay an egg the next day. No way in hell was her body able to produce albumin, shell and lay the same yolk her mate fertilized. But birds can’t apply logic like that, and her mate behaves as if she was monogamous – fighting away other birds, keeping her in the nest until she lays, etc.