Recently, I was discussing the relative virtues of four-door and two-door cars with a friend. I prefer four-door cars, because they make it much easier for back-seat passengers to get in and out (they make it easier to access the back seat, in general). My friend prefers two-door cars, because he seldom has back-seat passengers, and the larger doors of two-door cars make it easier for the front-seat occupants to get in and out.

“But,” I say, “on a two-door car, the doors are larger and heavier.

A lack of Vitamin D, due to reduced sunlight, has been linked to depression and the symptoms of Seasonal Affective Disorder (SAD), but research by the University of Warwick shows there is no clear link between the levels of vitamin D in the blood and depression.

Exposure to sunlight stimulates vitamin D in the skin and a shortage of sunlight in the winter has been put forward as one possible cause of SAD. However Warwick Medical School researchers, led by Dr Oscar Franco, have discovered low levels of vitamin D in the blood may not be connected to depression.

The International Institute for Species Exploration at Arizona State University and an international committee of taxonomists – scientists responsible for species exploration and classification – today announce the top 10 new species for 2009, consisting of those described in 2008.

On the list are a pea-sized seahorse, caffeine-free coffee and bacteria that live in hairspray. The top 10 new species also include the very tiny (a snake just a slither longer than 4 inches or 104 millimeters), the very long (an insect from Malaysia with an overall length of 22.3 inches or 56.7 centimeters) the very old (a fossilized specimen of the oldest known live-bearing vertebrate) and the very twisted (a snail whose shell twists around four axes).