Thanks to their robust bones, which fossilise better than those of most other birds, we have a fairly good record of the evolutionary history of penguins.
The earliest remains of Waimanu manneringi, a 1.2-metre-tall bird – similar in size to an Emperor Penguin – date back more than 60 million years. Gerald Mayr and colleagues recently reported that an even larger species, standing about 1.5 metres tall, also occurred in New Zealand at about the same time as W. manneringi (2017, Science of Nature 104: 9). Interestingly, the newly described species shows several features typical of more ‘advanced’ penguins, suggesting that penguins radiated rapidly after the Cretaceous- Palaeogene mass extinction that saw the demise of the non-avian dinosaurs. At least 12 more species of ‘giant’ penguins flourished for almost 30 million years. Their disappearance during the Oligocene more or less coincided with the evolution of toothed whales and dolphins, giving rise to speculation that either competition with or predation by these marine mammals (or perhaps a combination of both) led to the giant penguins’ demise.
هذه القصة مأخوذة من طبعة July - August 2017 من African Birdlife.
ابدأ النسخة التجريبية المجانية من Magzter GOLD لمدة 7 أيام للوصول إلى آلاف القصص المتميزة المنسقة وأكثر من 9,000 مجلة وصحيفة.
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هذه القصة مأخوذة من طبعة July - August 2017 من African Birdlife.
ابدأ النسخة التجريبية المجانية من Magzter GOLD لمدة 7 أيام للوصول إلى آلاف القصص المتميزة المنسقة وأكثر من 9,000 مجلة وصحيفة.
بالفعل مشترك? تسجيل الدخول
EXPLORING NEW HORIZONS
Keith Barnes, co-author of the new Field Guide to Birds of Greater Southern Africa, chats about the long-neglected birding regions just north of the Kunene and Zambezi, getting back to watching birds and the vulture that changed his life.
footloose IN FYNBOS
The Walker Bay Diversity Trail is a leisurely hike with a multitude of flowers, feathers and flavours along the way.
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How photographing birds helps me face adversity
CAPE crusade
The Cape Bird Club/City of Cape Town Birding Big Year Challenge
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.
flood impact on wetland birds
One of the features of a warming planet is increasingly erratic rainfall; years of drought followed by devastating floods. Fortunately, many waterbirds are pre-adapted to cope with such extremes, especially in southern Africa where they have evolved to exploit episodic rainfall events in semi-arid and arid regions. But how do waterbirds respond to floods in areas where rainfall - and access to water - is more predictable? Peter Ryan explores the consequences of recent floods on the birds of the Western Cape's Olifants River valley.
a star is born
It’s every producer’s dream to plan a wildlife television series and pick the right characters before filming.
