Transcript Acquired Variation

Within a species, there is usually a great deal
of variation among individuals.
Human Variation
There are variations in skin color, hair color,
hair curliness, eye color, blood type, height, etc.
Inherited Variation
Results from
differences in
DNA, genes
Genetic
Variations
cannot be
changed*
*mutations
ex: hair color,
eye color,
blood type,
hair on middigits
Inherited Variation
Passed on to offspring
Sources of Genetic Variation
Gene Shuffling
Mutations
Sexual reproduction;
different combinations/
expressions of genes
Errors in DNA copying,
environmental damage
Acquired Variation
Results from
individual
activities,
environments
Is not
passed on
to offspring
ex. body
figure,
certain skills,
tattoos,
piercings
North side,
upper branches
South side,
upper branches
Apples collected
from different
positions on the
same tree.
The differences
between apples
are acquired
during the growing
season.
North side,
lower branches
South side,
lower branches
Difference will not
be inherited.
Most differences in a species are the result of
inherited and acquired variations.
low variance
Cheetahs
Manatees
high variance
Leopards
Cuttlefish
If a major disease swept through both populations,
which species would have higher rates of survival?
SWEATY SHIRT EXPERIMENT
 Clause Wedekind
 1998
 Bern University in
Switzerland
 49 men wore the same shirt for 2 days
 44 women were asked to rank the shirts in order of smell preference
 the scientists measured the MHC genes (genes related to smell) of each male
and each female
 the results found that women preferred shirt smells from males who had the
most different MHC genes from their own
 Women preferred males whose paired offspring would have the greatest
genetic variation