The demands of incubating eggs and feeding a brood of chicks results in most birds forming partnerships to breed. In most cases, these are simple male-female pairings, which explains why most birds are at least socially monogamous. By comparison, most mammals are polygynous, with one sex – usually the female – left to rear the offspring alone. But some birds take group living a step further, involving more than two birds in raising the offspring. Such species are termed cooperative breeders and the phenomenon is particularly common among birds breeding in southern Africa and Australia.
Living in groups brings its own challenges, including the need to develop and maintain social bonds. It has long been argued that social interactions are a key driver of the evolution of ‘intelligence’. Correlative studies suggest that social birds and mammals have better cognitive abilities and increased brain capacity compared to solitary species and experimental studies show that brain structure is related to group size in captive monkeys and even fish, but only recently has this been demonstrated in free-living animals.
この記事は African Birdlife の July/August 2021 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、8,500 以上の雑誌や新聞にアクセスしてください。
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この記事は African Birdlife の July/August 2021 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、8,500 以上の雑誌や新聞にアクセスしてください。
すでに購読者です? サインイン
footloose IN FYNBOS
The Walker Bay Diversity Trail is a leisurely hike with a multitude of flowers, feathers and flavours along the way.
water & WINGS
WATER IS LIFE. As wildlife photographer Greg du Toit knows better than most.
winter wanderer
as summer becomes a memory in the south, the skies are a little quieter as the migrants have returned to the warming north. But one bird endemic to the southern African region takes its own little winter journey.
when perfect isn't enough
Egg signatures and forgeries in the cuckoo-drongo arms race
Southern SIGHTINGS
The late summer period naturally started quietening down after the midsummer excitement, but there were still some classy rarities on offer for birders all over the subregion. As always, none of the records included here have been adjudicated by any of the subregion's Rarities Committees.
prey for penguins
To stem the African Penguin's slide to extinction, government support for optimal no-take zones around South Africa's penguin colonies is critical.
agrochemicals and birds
By the year 2050, it is estimated that 171 million more hectares of agricultural land will be needed to feed a global population of 10 billion people.
arrivals and departures
The Mouse-Free Marion Project is committed to ensuring that breeding seabirds can return to a predator-free Marion Island.
MIDRAND marvel
Gauteng birders don't need to travel far to get their feathery fix. Midway between Johannesburg and Pretoria, Glen Austin Pan has become a favourite patch for this returnee expat.
a journey through the mysteries of moult
As a bird researcher in South Africa’s botanically diverse fynbos biome, I have come to regard bird ringing as part of my journey to understanding moult.
