YOU ARE LEARNING:
The theory of speciation was initiated by Alfred Wallace, which describes how new species are formed.
Dogs from different breeds, (Huskies, Jack-Russel etc.) all look very different, but they can cross-breed to produce young that can breed and have young. So all dogs are part of the same species.
The same is true of cats and many other domestic animals.
Sheep of different breeds can be inter-bred to produce new breeds that can also reproduce. Choose the most accurate option below.
A horse and a donkey can be bred to produce offspring called mules. Mules cannot breed. They are all infertile. Why is this?
Pick the most accurate definition of what a species is.
Which of the following are examples of species? Answer with yes or no only.
The theory that explains how organism change over time is called...
Many ideas in science result from work by many different people. Evolution by natural selection was famously credited to Charles Darwin, but he used other people's ideas, including those of Erasmus Darwin and Alfred Russell Wallace. Wallace and Darwin came up with the modern idea of evolution independently of each other.
Wallace travelled across the world collecting samples and drawings of tens of thousands of species. He was inspired to develop the idea of evolution by natural selection from this work.
Which of the following made Wallace a good scientist? Pick all the options you think are correct.
You can select multiple answers
A few quick facts on Alfred Russell Wallace
in Wales, and educated in Hertford (Richard Hale School).
across the world, but mainly in Asia.
Famous for ...
- Co-discovery of evolution by natural selection
- Developing the theory of Speciation
- Putting forward ideas on warning colours in animals (for example black and yellow in bees and wasps etc.)
Darwin travelled for 5 years and then developed his ideas in England, where he presented them to The Royal Society and at Oxford University. Wallace worked in East Asia and published his ideas from there.
Why do you think Darwin became more famous than Wallace?
Definition of speciation
The process that leads to a new species.
A species can evolve and change without creating a whole new species.
In fact, as long as organisms can all interbreed and move around freely, it's rather unlikely that a new species would be formed.
But what if part of a species becomes isolated from the rest? What if there was a flood or an earthquake for example that cut a group of the individuals off from the rest and forced them to live somewhere new? Might the group that was cut off have to adjust to a new environment? Answer yes or no.
The new location could be a new or changed environment. It could be hotter, colder, there could be new food sources etc. Now, would the two groups evolve to become similar or different?
Because the two populations develop to adjust to different environments, and because their genes cannot mix because they are isolated from each other, a new species will gradually form.
This is speciation!
Iguanas are a type of lizard found across South America. On the mainland they hunt in vegetation and on rocks. They never hunt in the sea. On the Galapagos Islands, 1000 km off the mainland, however, there is a species that has adapted to hunt in the ocean. Why, do you think?