evolution
By Arathi Anand
topic five
5. I -
evidence for evolution
5. 2- natural selection
5. 3- Classification of biodiversity
5. 4- Cladistics
, 5.1 evidence of evolution
is / 1012020
evolution cumulative change in the heritable characteristics or-
a
population
Cumulative change small many generations
° -
:
change over
0 Heritable characteristics :
gene - controlled factors
they heritable traits alleles in an
o
These traits cannot be acquired over a lifetime ,
are or
organism 's DNA .
evidence
of evolution Fossil records
0 Fossils -
sedimentary rocks °
Fossils are the preserved remains of animals , plants , and other organisms from the
past
HÉgxe
° .
☐
The fossil record shows the gradual change of species over time
°
Vestigial structure e.
g. appendix 0
The timeline in which fossils scientists would expect , with
appear are what
•
selective breeding bacteria andalgae being the in the fossil record .
Followed later by
thermals and Ibis , then dinosaurs and early reptiles birds and
o
comparative DNA ,
mammals later still .
°
Observable change
°
Relative Dating : rocks the bottom are older than the rocks near the top
at
.
( not very accurate at different rocks form / erode at dirrerent rates ) .
and throughout the yea ,
selective breeding Caniriciai selection ) Radioactive Dating rocks contain radioactive elements
°
:
elements in the end than started
these elements decay →
leaving less radioactive
.
0
breeding plants and animals for specific genetic trails
0
shows a good record of recent changes in genetic characteristics over a few dozens of generations that man has selected to breed .
°
For example ,
chickens that produce more eggs or cows that produce more milk are selected to breed , hopefully passing these traits onto the next .
generations .
based useful beneficial characteristics breeders would like to see in the next generation
°
plants can be bred in a similar manner on on
of plants .
breeds through artificial selection
☐ The evolution of domesticated dogs has produced many .
homologous structure ( similar structures found in dissimilar species )
common internal structures that are similar in seemingly dissimilar animals evolved
0
that have from a common ancestor .
•
The standard example of homologous structure is the
pentadactyl limb which is the five digit limb found in animals such as
humans , dolphins, bats
,
and dogs .
and function of this structure vary between structure and position of the bones in these
o Even
though the shape ,
size
species , the general
limbs are the same .
By Arathi Anand
topic five
5. I -
evidence for evolution
5. 2- natural selection
5. 3- Classification of biodiversity
5. 4- Cladistics
, 5.1 evidence of evolution
is / 1012020
evolution cumulative change in the heritable characteristics or-
a
population
Cumulative change small many generations
° -
:
change over
0 Heritable characteristics :
gene - controlled factors
they heritable traits alleles in an
o
These traits cannot be acquired over a lifetime ,
are or
organism 's DNA .
evidence
of evolution Fossil records
0 Fossils -
sedimentary rocks °
Fossils are the preserved remains of animals , plants , and other organisms from the
past
HÉgxe
° .
☐
The fossil record shows the gradual change of species over time
°
Vestigial structure e.
g. appendix 0
The timeline in which fossils scientists would expect , with
appear are what
•
selective breeding bacteria andalgae being the in the fossil record .
Followed later by
thermals and Ibis , then dinosaurs and early reptiles birds and
o
comparative DNA ,
mammals later still .
°
Observable change
°
Relative Dating : rocks the bottom are older than the rocks near the top
at
.
( not very accurate at different rocks form / erode at dirrerent rates ) .
and throughout the yea ,
selective breeding Caniriciai selection ) Radioactive Dating rocks contain radioactive elements
°
:
elements in the end than started
these elements decay →
leaving less radioactive
.
0
breeding plants and animals for specific genetic trails
0
shows a good record of recent changes in genetic characteristics over a few dozens of generations that man has selected to breed .
°
For example ,
chickens that produce more eggs or cows that produce more milk are selected to breed , hopefully passing these traits onto the next .
generations .
based useful beneficial characteristics breeders would like to see in the next generation
°
plants can be bred in a similar manner on on
of plants .
breeds through artificial selection
☐ The evolution of domesticated dogs has produced many .
homologous structure ( similar structures found in dissimilar species )
common internal structures that are similar in seemingly dissimilar animals evolved
0
that have from a common ancestor .
•
The standard example of homologous structure is the
pentadactyl limb which is the five digit limb found in animals such as
humans , dolphins, bats
,
and dogs .
and function of this structure vary between structure and position of the bones in these
o Even
though the shape ,
size
species , the general
limbs are the same .