What's the buzz...

Why giraffes have long necks

The giraffe’s long neck may have evolved to help the male compete for mates, suggests new research.

Nearly 15 million years ago the giraffes were antelope-like animals roaming the dry grasslands of Africa. They had no distinguishing characteristics, except that some of their necks were a bit long.

But within 6 million years, they had evolved into animals that looked like modern giraffes, even as we know the modern species only emerged around 1 million years ago. Today’s giraffe, the tallest living land animal, stands between 4.5 and 5 metres tall with its neck making up nearly half that height.

It is largely believed that giraffes’ long necks evolved to help them eat leaves on tall trees that their rivals couldn’t reach.

But the evidence supporting the high-feeding theory is surprisingly weak. The latest theory is that the long necks are the result of sexual selection — they evolved in males as a way of competing for females.

Male giraffes fight for females by ‘necking’. They stand side by side and swing the backs of their heads into each others’ ribs and legs. Helping them are their unusually thick skulls and horn-like growths called ossicones on the tops of their heads.

A long and powerful neck would be an advantage in these duels, and it has emerged males with long necks tend to win, and also that females prefer them.

The ‘necks for sex’ idea also answers why giraffes have extended their necks so much more than their legs. If giraffes’ long necks evolved to reach higher branches, their legs should have been lengthened as fast as their necks, but they haven’t.

System that locates, guides drivers to car park spaces
Spanish researchers have developed a new system which locates unoccupied car park spaces and guides users to the nearest one.

The new network of sensors for the management of public car parks and locations, which researchers have named XALOC (Xarxes de sensors per a la gestió d'Aparcaments públics i LOCalització), was developed by a consortium formed by the firm WorldSensing (consortium leader) and the Centre for Telecommunications Technology of Catalonia (CTTC).

The project’s consortium developed a platform based on a network of wireless sensors capable of detecting unoccupied spaces outdoors, and on an alternative positioning system with more precision in urban areas than GPS technology. This platform is capable of locating and guiding drivers to car park spaces available in the area.

The network’s sensors are located on the ground directly in the middle of the car park space. The sensors detect whether the space is occupied or not and send information via internet to a central station. The server processes this information and sends it to indication panels located in the street which display the information in real time. Advanced communication techniques are used to send guidance data to the network.
The sensor platform at the same time locates users looking to park and thus offers a personalised service.

Solar lamp wins award for helping developing countries
A company, run by Indian entrepreneurs, has won a prestigious environmental award for designing a solar lamp that aims to replace kerosene-burning lights in developing countries. D Light Design says its lanterns, which sell for around 10 dollars, contribute to the reduction of carbon emissions.

One of the runners-up for the Ashden Award for Sustainable Energy was the Rural Energy Foundation (REF) for promoting solar energy in Africa. More than 70 per cent of sub-Saharan Africa has no access to electricity.

D Light has won the 40,000 pound Gold Award, for “its passion and dedication to the cause of ridding the developing world of the health and pollution problems associated with the use of kerosene lighting”, said the judges. The company said that indoor air pollution by Kerosene fumes kills 1.5m people per year.

“This will do to kerosene what mobile phones did to letters,” said one of the entrepreneurs.

DH Newsletter Privacy Policy Get top news in your inbox daily
GET IT
Comments (+)