Whales & dolphins: a Museum guide
Our Finback Whale
The Museum’s Finback Whale skeleton hangs above the main entrance. It was exhibited in the Old Zoology Museum before the building was demolished in 1965. The New Zoology Museum was designed so that the Whale, an important teaching exhibit, should also advertise the Museum’s presence – it is spotlit at night.
The Finback Whale is the second largest living whale, exceeded in size only by the Blue Whale, and the Cambridge specimen is also one of the largest recorded of its species, with a length of over 21 metres and a weight in life of 80 tonnes (as large as the heaviest dinosaurs). It is truly an emblematic animal and draws visitors’ attention to a heritage of collections and the University’s responsibility of caring for them.
The Finback Whale, a male, was washed ashore dead at Pevensey in Sussex in November 1865. Around 40,000 people are estimated to have made the trip to view it on the beach during the first few days. The skeleton was prepared and put on public display over Easter 1866 on Hastings Cricket Ground, and was subsequently bought for the Museum by public subscription. Please feel free to go up to the podium to have a closer look.
Whales, dolphins and porpoises comprise an order of mammals called the Cetacea. There are around 77 species of living cetaceans. Fossil finds indicate that, as long suspected, the closest living relatives to the cetaceans are the ‘even-toed ungulates’ such as pigs, cattle, hippopotamuses, giraffes, camels, antelopes and deer. More recent research claims that cetaceans are related specifically to the hippopotamus.
There are two types of whale – those with teeth and those without. The two sorts of whales, toothed and whalebone, appear to have been separate in evolutionary terms since at least 40 million years ago. The family to which our Finback Whale belongs, the Balaenopteridae, also contains the Blue Whale, the Humpback Whale and the Minke Whale, among others. All of these are ‘mysticetes’, or so-called ‘whalebone’ or ‘baleen’ whales with fringed plates in their mouths to strain out food material from the water. A sweep of the tongue collects the food.
Whalebone is self-renewing, growing downwards from the top and splitting into fibres at the bottom. The large triangular-shaped exhibit running along the base of the cabinet in the lower gallery is a whalebone from a Greenland Right Whale, and is the type of material once used in corsets.
The other major grouping of whales, the odontocetes or ‘toothed whales’, includes Sperm Whales, dolphins and porpoises and, hanging from the gallery roof, the Killer Whale, Bottle-nosed Whale, Beaked Whale and especially the curious Narwhal, Monodon monoceros (‘one-tooth, one-horn’). Despite its Latin name, our Narwhal is abnormal in having two tusks.
There are other specimens of Cetacea in the case in the lower gallery. Look for a whole skeleton of a Common Dolphin, together with its skeleton. There is also a skeleton of the Ganges River Dolphin, a freshwater species which inhabits the rivers of India and which is almost blind, only able to distinguish vague shapes and light from dark.
Examining the dolphin skulls end on, you can see that they are quite asymmetrical. The bones have evolved this way to aid direction finding by sonar – the dolphin’s sonar blips return back to its head at very slightly different times from different directions. This is known as echo-location. Also look at the neck vertebrae of a whale – nearly all mammals have seven neck vertebrae, and so do whales, although their neck region is very shortened and the neck bones are therefore compressed in appearance.
Something of the biology of the large baleen whales may be appreciated by considering the Finback in particular. In life, Finbacks are usually grey or brownish on their backs and pale on their bellies, with a short fin on the back quite close to the animal’s tail. There is an interesting asymmetry in coloration – the right side of the jaw is pale, whereas the left side is darker. Strangely, this pigmentation is also shown on the tongue.
Finback Whales occur in small groups or may be solitary. They are typically whales of the open seas and are found in all oceans. They are very fast-swimming creatures, and show similar migratory patterns to Blue Whales, with a general northwards movement of southern animals into warmer waters for breeding during the southern winter season. After breeding, the whales return to the Antarctic.
Finbacks eat small crustaceans and schooling fishes such as herring, together with squid. Like other whalebone whales, Finbacks feed by using their baleen, the fringed plates on both sides of the mouth, as a strainer. There may be over four hundred plates on each side, each some seventy centimetreslong. These plates are on the upper jaws only. The lower jaws are bowed outwards, and are joined together by ligaments attheir front ends to give some flexibility of movement.
The throats of whalebone whales are pleated, allowing an enormous expansion of the throat cavity when water is taken in to be strained. The mouth itself can be opened very wide and, together with the expansion of the throat, tonnes of water are strained through the baleen every time the whale takes a mouthful.
Finbacks become sexually mature at around ten to thirteen years old. Calves are born after an eleven-month period of gestation, and are suckled for about six months. At birth a Finback Whale calf weighs 1.8 tonnes and is around 6.5 metres long.
It is our hope that our Finback Whale skeleton will make its point to visitors of all ages. Many species of whale, including the Finback are regarded as endangered. It is important that everyone should become aware of what amazing creatures we stand to lose as a result of unrestricted whaling and the consequences of failure of international co-operation in this field.