Download Speciation - Noadswood Science

SPECIATION
L.O: To understand how isolation, genetic
variation, natural selection and speciation can
cause new species to arise
List animals that only live in Australia.
Why do they only exist in Australia?
Copy and complete selecting the correct words
from below
A species is a group of _________ organisms that can
produce offspring which also ___________ able to
reproduce.
different
will be
will not be similar
How do species become isolated?
Physical isolation
Geographic isolation
Natural selection
Complete the Madagascar worksheet
The rise of new species
Over time, new species evolve from earlier species. This may happen for
a variety of reasons.
Populations of one species may become geographically
isolated from one another.
Genetic variation means that individuals of a
population have many different alleles that result
in different characteristics.
The process of natural selection means that individuals with beneficial
characteristics will survive and reproduce.
Eventually, populations can become so different that they can no longer
interbreed. This is called speciation.
Darwins Finches - A historical
theory
Modern Day examples
- Californian Salamander
- Central European Blackcap
- Lake Malawi fish
How do these examples of speciation support Darwin’s
theory?
Natural selection leads to evolution
Pollution and a new predator in Lake Victoria have reduced
the number of fish species. However a new species has
been discovered that has much larger gills. This enables
the new species to live in polluted muddy water where
other species, and the predator cannot live. Outline how
this new species evolved.