This skull is from a goliath heron, a large aquatic bird that lives in Africa.
What to see
This is the skull of a goliath heron (Ardea goliath). It is part of the F.W. Lucas osteological (bone) collection donated to Brighton Museum in the early 20th The goliath heron is the largest living species of heron in the world, and is found in sub-Saharan Africa. Though it is not endangered, they are more aquatic than other herons spending almost all their time in or around water. They also prefer undeveloped waterways away from human activity, so are threatened by increasing human populations.
The long, sharp beak seen in herons is an evolutionary adaptation to their environment and way of life. Because of their size, goliath heron’s tend to ignore small prey and specialise in larger fish, and the beak has evolved to act like a spear. Goliath herons often use the closed beak to spear through a fish. They will then usually land the fish and let it die on land before swallowing it whole. This manner of catching and landing their prey makes them vulnerable to kleptoparisitism, where other birds such as fish eagles and pelicans will steal their prey.
Look at the bone structure inside the skull. You can see that instead of the bone being solid (as mammal bones are) it is actually a web like structure of criss-crossing bony filaments. This structure is seen in all birds and works to the birds advantage in two main ways. Firstly, the web structure creates a framework of geometric shapes which resist compression (much like the trusses on a bridge). This allows the bones to be strong but lightweight. This strong, lightweight feature of the skeleton provides the main advantage to birds – a light enough bodyweight to allow them to fly.
Finally if you zoom in closer you can see thin, root like markings on the bones of the beak. These markings are the imprint of blood vessels. These blood vessels run under the hard sheath of the beak in life, keeping the sheath nourished and healthy. Alongside these blood vessels run millions of sensory nerves. These make the beak an important sensory tool for birds, and as the beak is their main method of manipulating their environment it is another reason the beak is covered with a hard, keratinous outer sheath, similar to your fingernails.
Author: Lee Ismail, Curator of Natural Sciences