Species

Species:

A Species is a group of organisms that can interbreed (reproduce with one another) to produce offspring that are fertile (able to reproduce).

But sometimes two closely related species can breed and produce Hybrids. Hybrids aren't one species nor the other which show characteristics from both parents. Hybrids are usually infertile (unlikely to have offspring of their own).

Neighboroughing populations of the same species may have slightly different characteristics but still interbreed. Sometimes there's a chain of different populations that can all breed with their neighboroughing population BUT the two populations at either end of the chain
can NOT interbreed. These organisms are called ring species.

An organism's scientific name has two latin words, the Genus and Species. This is called the Binomial System. Organisms that share the first word in their name are closely related.
Binomial System is also useful because those with the same common names may actually be a different species. E.g. The robin in America isn't the same species as a robin in the UK.
The system is a way of scientists around the world to be able to communicate.


Key Words:

Species
Interbreed
Fertile
Hybrids
Ring Species
Binomial System


Define these in your revision notes.


Questions:

1. Why can't American and British Robins interbreed?
2. What is a Hybrid?
3. Why's it hard to divide populations that form ring species into separate species?
4. Why is the Binomial System useful?
5. Why is it difficult to define what we mean by the term 'species'?


What you Should've learnt:

Why the definition of a species as organisms that produce fertile offspring may have limitations; some organisms don't always reproduce sexually
and some hybrids are fertile.

Why Binomial Classification is needed to identify and study species.

Explain how accurate classification may be complicated by: b. Hybridisation in ducks c. Ring species.

The role of the scientific community in validating new evidence, including the use of: a. Scientific journals b. the peer review process c. Scientific
conferences.