· Term biodiversity encompasses variety of biological life at more than one scale. It is not only the variety of species (both plant and animal) but also the variety of genes with those species and the variety of ecosystem in which the species reside.
· Biodiversity or biological diversity; is the variety of life on earth across all the different levels of biological organization. Biodiversity can be used to describe the variety in the genetic makeup of a species and on a larger scale; it can be used to describe the variety of ecosystem types.
· According to CBD( Convention on Biological Diversity); Biological diversity means the variability among living organisms from all sources including interalie terrestrial, aquatic and marine ecosystem and ecological complexes of which they are a part, this includes diversity within species between species and of ecosystem.
Types of biodiversity:
Biodiversity is divided into three categories:
1) Species diversity: It is defined as the number and abundance of different species that occupy a location. To accurately determine species diversity, both the species richness which is the number of individuals within each species; it must be considered. For example; Number and abundance of different types of mammals in forest.
2) Genetic diversity: It is the amount of variation in genetic material within a species or within a population. There is high level of diversity among species, but there is an even higher level of diversity among the genetic material of the individuals of specific species. For example, Variation in the genes that encode for hair color in humans.
3) Ecological diversity: Variation in ecosystem found in a region or over the whole planet. It includes variation in both terrestrial and aquatic ecosystem. It also takes into account the variation in the complexity of biological community, including the number of different niches, the number of trophic levels and other biological processes. For example: variation in ecosystem such as desert, forest, grasslands, wetlands and ocean.
Facts about biodiversity:
Ø Researchers have estimated that there are between 3-30 million species on earth, with a few studies predicting that there may be over 100 million species on earth. We have identified only 1.7 million species.
Ø There is more biodiversity within tropical ecosystem than temperate or boreal ecosystem. Tropical rain forest has most diversity.
Ø The most diverse group of animals are invertebrates. They are animals without backbone including crustaceans, sponges, scorpions and many other kind of organism. Over half of all the animals already identified as invertebrates. Beetles are some of the most.
Ø Science has so much more to learn about the biodiversity of microscopic organisms like bacteria and protozoa.
Importance of biodiversity:
Ø It allows us to live healthy and happy lives. It provides us with an array of foods and material and it contribute to the economy.
Ø Most medical discoveries to cure diseases and lengthen life spans were made because of research into plant and animal biology and genetics. Every time a species goes extinct; we will never know whether research would have given us new vaccines and drugs.
Ø Biodiversity is important part of ecological survive that make life live able on earth. They includes everything from cleaning water and absorbing chemicals which wetlands do to provide oxygen us to breathe one of many things that plants do for people.
Ø Biodiversity allows for ecosystem to adjust the disturbances like extreme fires and floods. If reptile species go extinct, a forest with 20 other reptiles is likely to adapt better than another forest with only one reptile.
Ø Genetic diversity prevents diseases and help species to adjust with the changes in their environment.
Ø There are few things as beautiful and inspiring us the diversity of life that exists on earth.
Threats to biodiversity:
Extinction is natural part of life on earth. Species go extinct because of natural shifts in the environment that take place over long periods of time such as ice cages. Today species are going extinct at an accelerated and dangerous rate because of non- natural environmental changes caused by human activities. Some of the activities have direct effects on species and ecosystems. Such as-
· Habitat loss or degradation
· Over exploitation
· Spread of non- native species or disease
Some human activities have indirect but wide reaching effect on biodiversity including-
· Climate change
According to IUCN (International union for conservation of nature) globally about 1/3 of all known species are threatened with extinction, that includes 29% of all mammals and 12% of all birds.
Biological resources includes genetic resources, organisms and parts there of populations, or any other biotic component of ecosystem with actual or potential use or value for humanity.
Living organisms are classified to arrange them in systematic format. Classification is needed because it allows scientists to identify group and properly name organism.
Museum is an institution where artistic and educational materials are exhibited to the public, the material available in exhibition for study is called collection.
Herbarium is a place where dried and pressed plants, specimens, mounted on sheets are kept systematically. It was established by Luca Ghini.
Zoological parks are places where wild animals are kept in protected environment under human core and which enable us to learn about their food habits and behavior.
Botanical gardens are institutions holding documented collections of living plants for the purpose of scientific research, conservation, display and education.
Species is the lowest category of hierarchy. Taxonomic hierarchy is the arrangement of various categories in successive levels of the biological classification.