THESE days low-lying wetlands, bogs and wet woodlands are habitats which are under threat from the pressure of mankind.

In the past century many thousands of hectares of these types of land have been lost from Worcestershire, only leaving a tiny percentage of what were once extensive areas of wetland along the major river valleys.

Wetland was an easy target when it came to changing its land use.

Due to their rich river alluvium deposits, wetlands are highly fertile areas, and by the simple act of digging drainage ditches it was possible to turn them into highly productive agricultural land - and this was the fate of vast areas of this habitat.

The utilisation of the rich wetland soils may have helped feed the rapid growth of the human population, not just here in England, but throughout the world.

However, we owe wetlands a debt of gratitude which extends much deeper, as if it was not for this type of habitat, modern life would not be the same. Who knows, humans and even land-living vertebrate life may never have evolved.

These days we rely heavily on petrol and other oil-based products.

The crude oil from which all these are manufactured started off as wet swampland.

Back in the Cambrian period before the dinosaurs - some 350 million years ago - large areas of lowland were covered by marsh.

These early marshes were filled with abundant plant and insect life and over the years these died and were buried by silts and, in a similar way to how the bones of the dinosaurs turned into fossils, these Cambrian bogs turned into the oil and gas products we rely on today.

It was also in these Cambrian bogs that life took a twist which eventually led to the evolution of humans.

Back in the Cambrian period the first vertebrates, or back-boned animals, started to evolve.

Initially this took place out in the open seas with the evolution of many species of fish.

Fish proved to be a highly successful design and many thousands of different species evolved.

Some of these managed to find their way into rivers and even into the rich wetland habitats.

However, for a fish, a wetland is no easy place to live. Despite the abundance of food wetlands, by their nature, dry up, and this can easily lead to the fish becoming beached or having to cope with de-oxygenated water.

In circumstances like this the pressures for evolutionary adaptation are extreme and fish over the millions of years evolved some of our most important physical attributes in order to adapt to these primeval swamps - lungs to breathe oxygen from the air, and limbs to clamber over the drying land.

From these early fish evolved the amphibians, who were even better equipped to deal with life in the wetlands and from these the reptiles and the mammals evolved, and from these, eventually - us.