Bird Collection: Bittern

This Bittern is part of our Science Department Collection.

Scientific name: Botaurus stellaris

The bittern is a thickset heron with all-over bright, pale, buffy-brown plumage covered with dark streaks and bars. It flies on broad, rounded, bowed wings. A secretive bird, very difficult to see, as it moves silently through reeds at water's edge, looking for fish. The males make a remarkable far-carrying, booming sound in spring.
It's very small, reedbed-dependent population make it an Amber List species.


Nautical Sextant

This nautical sextant is part of our Science Department collection.

A sextant is an instrument that measures the angle between two objects that are visible. Primarily, it is used to measure the angle between a celestial body and the horizon. The angle measured and the time at which it was measured is then used to identify the location of the user on the grid map of the world. 

The principle of the instrument was invented by Sir Isaac Newton during his life time but the actual tool was developed later on by John Hadley and Thomas Godfrey in 1730.

The sextant consists of a telescope, a horizontal mirror which the telescope "looks" through, and a moving arm on which the index mirror is fixed. By manipulating this arm a star or other celestial body can be made to appear on the horizon. Accurate adjustments are made by means of a micrometer knob. The angle can then be read off the arc and micrometer. The shades are used when the object being looked at is bright - such as the sun.


Stenopterygius skull

This is a replica fossil of a "stenopterygius skull" of a juvenile icthyosaur. It is an extinct genus of thunnosaur ichthyosaur known from Europe. it is part of the Science Department collection.

Its skull was extended into a kind of a beak and was armed with a quantity of large teeth. 

It spent most of its life in the open sea, where it hunted fish and other animals. The abdominal cavity of skeletons of this ichthyosaur often contains the remains of such food. One famous fossil is that of a mother and baby that died in childbirth. This proved that ichthyosaur infants were born tail-first, to prevent them from drowning before fully clearing the birth canal.

Stenopterygius was a very fast swimmer, with a cruising speed similar to that of tuna, which is among the fastest of all living fishes.


Protolindenia Wittei Dragonfly

This is a replica fossil of a "protolindenia wittei" dragonfly that lived in the Jurassic period around 135 million years ago. These dragonflies had wingspans of about 15cm. It is part of the Science Department collection.
 
Adult dragonflies are characterized by large multifaceted eyes, and two pairs of strong transparent wings, sometimes with coloured patches and an elongated body. Many dragonflies have brilliant iridescent or metallic colours, making them conspicuous in flight.
 
Fossils of very large dragonfly ancestors have been found from 325 million years ago (Mya) in Upper Carboniferous rocks; these had wingspans up to about 75cm.
 
Dragonflies are represented in human culture on artifacts such as pottery, rock paintings, and Art Nouveau jewellery. They are used in traditional medicine in Japan and China, and caught for food in Indonesia. They are symbols of courage, strength, and happiness in Japan, but seen as sinister in European folklore.