Is the penguin really a monogamous system that 'takes care of one companion in a lifetime'?

Penguins gather in one place during the breeding season and form a collective breeding area called a 'colony'. In this colony, males build nests and mate with their own mates, while females lay eggs. It is said that males and females always join their mates during the breeding season and only pair with one mate. Live Science, a scientific news site, explains the monogamy of this penguin.

Are penguins really monogamous? | Live Science

Penguins adopt monogamy socially because they need a dedicated partner to efficiently share nest maintenance, egg hatching, hunting, etc. in a harsh environment like Antarctica. It seems that it is because

'Social monogamy is a prerequisite,' says Emma Marks, a behavioral ecologist at the University of Auckland. Breeding will fail,' he said.

However, according to LiveScience, the strength of the notion of chastity varies greatly among species, with many species only pairing with one mate during breeding season, but some having multiple mates before nesting. It is said that they sometimes mate with other penguins.

A study published in 2013 found that 89% of Galapagos penguins mate with a specific partner during the breeding season, and 59% to 89% of penguins of other species mate with a specific partner. About. On the other hand, a 1999 study reported that only 15% of emperor penguins were looking for a specific partner during the breeding season. ``Colonial birds like penguins may be monogamous, but that doesn't mean that extracurricular activities aren't being done,'' Marks said.

According to Marks, penguins are socially monogamous, but not sexually monogamous. It seems that there is also a development similar to humans in which the original partner finds out that he has mated with another penguin that already has a pair, and develops a muddy love-hate drama.

For example, even when females return to the colony during the breeding season, there are cases where males to mate with killer whales have been eaten by killer whales or died of disease and never return. A widowed female penguin sometimes enters a nest with another male and cohabits without permission. About. And usually the female who was the original partner wins.

Also, in the case of males, it seems that it is not clear whether the chicks they are raising are really the offspring of the male.

A study published in 2018 observed a single male gentoo penguin in an aquarium in Utah. In this study, it is reported that the observed penguins raised two chicks, each descended from a different male, due to their partner's promiscuity with their peers.

Marks said whether penguin couples stay together long-term also has to do with their breeding success in the previous season. If the chicks can be safely raised to adulthood, and the male can maintain a high-quality nest in a good location, the female is more likely to return to her former partner. However, if breeding fails, there are cases of divorce in the next season.

Of course, not only bereavement and failure to raise chicks, but also food problems have a major impact on penguin breeding. For example, if the number of krill around the colony declines due to climate change or human fishing activities, the penguins will lose the colony they use to breed. Also, when sea ice and ocean currents change due to climate change, there are cases where penguins can no longer reach their colonies. It seems that the colony of Antarctica and Halley Bay , where 25,000 pairs of emperor penguins once gathered , has become barren since 2016 .

'Climate change may be reducing the success rate of breeding colonies, and high rates of breeding failures are always expected to lead to high divorce rates for penguin couples,' Marks said.

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