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Elephants: Why Are These Iconic African Animals Losing Their Tusks?
December 2021
|BBC Focus - Science & Technology
A genetic analysis suggests that African elephants are evolving to be tuskless, and it seems that poaching could be to blame
List an elephant’s most iconic characteristics and tusks should be right behind the long trunk, and arguably ahead of big ears and thick skin.
Tusks are elongated teeth that grow continuously and are used to dig for food and nutrients, clear paths through vegetation, mark or remove tree bark, and for fighting between males. The tusk can serve those diverse purposes thanks to the properties of its main material, ivory, which makes it strong and tough.
Ivory’s impressive properties make it attractive to humans. Traditionally used to make art and ornaments of cultural value, ivory has become a valuable status symbol. But as studies have shown, demand for ivory has helped to fuel a multibillion-dollar wildlife trade that encourages illegal hunting. And now new research has found that this may also have left an evolutionary mark on elephants.
A study by biologists at Princeton University looked at African savannah elephants in Mozambique’s Gorongosa National Park. During a civil war that lasted from 1977 to 1992, more than 90 per cent of large herbivores were slaughtered, including elephants. The elephant population dropped from more than 2,500 individuals 50 years ago, to less than 250 in 2000.
هذه القصة من طبعة December 2021 من BBC Focus - Science & Technology.
اشترك في Magzter GOLD للوصول إلى آلاف القصص المتميزة المنسقة، وأكثر من 9000 مجلة وصحيفة.
هل أنت مشترك بالفعل؟ تسجيل الدخول
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