Archive for category: News

In order to survive, all forms of life that we see around us have adopted a bizarre range of life strategies. I have recently been watching European common cranes spending the winter in southern France. Last March, we heard early arriving cuckoos in France calling in March!

This year, we watched several trios of cranes consisting of a male, female and one offspring feeding and preening together, getting ready for their long spring migration flight to northeast Europe. The youngsters were following their parents wherever they went looking for food, consisting of mainly unharvested maize seed heads and insects etc. When the time comes in February/March, the young birds follow their parents on migration towards Scandinavia and the Baltic states for the next breeding season. We watched a chevron of 35 cranes doing just that. During migration young birds separate from their parents and become independent, or get chased off when the parents start nesting. However, young cranes do not breed for several years, but still migrate to find sufficient food and, eventually, a mate and a nesting site.

In contrast to cranes, a cuckoo never knows it’s true parents, but still knows how to migrate and where and when to move. Not only that, but they also know to specialise in eating hairy caterpillars, a food that their surrogate parents never fed to them! All cuckoos are raised by surrogate parents whose nest has been used by a female cuckoo to lay a solitary egg in. Female cuckoos can lay from 12 to 22 eggs per year, each in a separate nest built by another bird species such as a reed warbler or meadow pipit for example. By the time the egg hatches, the adult cuckoos have left the area and will probably be migrating back to Africa. So, the nestling cuckoo will probably never even hear its parents calls, but will still know how to make those calls next spring. It is only the male that makes the familiar cuckoo call. Also, later in the year, the baby cuckoo will know exactly how to get to Africa for the winter without being taught how to get there by any other bird.

Herein lies the mystery of how much in animal behaviour is nurture and how much is inherited natural behaviour that can be described as some kind of genetic memory? Also, do we have any of this?

The science of Ecology is one of the newest academic disciplines taught at Universities, and did not really exist until about the 1950s. Prior to that, we had nature study, the sort of thing written about by the Reverend Gilbert White in the Natural History of Selbourne published in 1788-9. Prior to that we also had taxonomy (classification of living organisms) in the form of a book called Systema Naturae written by Carl Linnaeus and published in 1735. Later, we also had The Origin of Species written by Charles Darwin and published in 1859. However, most of this was natural history, and most of the animals that were studied were actually shot dead by the people writing about them. The plants were collected and dried and displayed in herbaria and the animals in natural history museums that also contained collections of pinned dead insects. Killing things was excusable and seen as sport.

During the 1950s and 60s wildflower and bird guidebooks started to appear. Then with television came programmes such as ‘Look’ with Peter Scott (son of Captain Scott of the Antarctic fame). We also had Johnny Morris at Bristol Zoo as a keeper and Desmond Morris with Zoo Time from 1956 and through the 1960s. Meanwhile, schools and universities were teaching Biology along with Physics, Chemistry and Geography, but the subject of Ecology never really emerged on its own until about the early 1970s. Ecology comes from the Greek words ‘oikos logos’ which mean ‘home study’. So, the science is the study of the ‘homes’ of plants, animals and other organisms such as fungi, bacteria, algae, slime moulds viruses etc. During this time, new kinds of books began to appear such as Rachel Carson’s Silent Spring which tells of a terrible world resulting from the over-use of pesticides resulting in the loss of all song-birds – hence ‘Silent Spring’. This book motivated biologists to start looking at the human (anthropogenic) effects of our activities on the natural world around us. Not only that, but we started studying the effects of one organism on another and produced the term ‘balance of nature’. We looked at the water and carbon cycle, trophic cascades and such things as density dependent mortality. Suddenly we had a mature science and just in time too, because if we did not, we would have run into the seriousness of human activity effects on the planet’s ecosystems completely blind.