Evolution 1
Set Created By: Mrs V Oberholzer
" Hypothesis : Initial idea that needs to be tested BEFORE
it can be accepted as possibly true
" Theory Set of well-tested and widely accepted ideas
that explain something in science, and is
supported by A LOT of evidence
" So, HYPOTHESIS first, then TESTING, it may be accepted as a THEORY
if it is NOT DISPROVED
THEORY 1: Lamarckism Jean-Baptiste Lamarck
Believed that individual organisms had the
ability to change their appearance
AND, that these changes be present in their
offspring
Proposed 2 laws for species to evolve: " The law of use and disuse:
" The law of inheritance of modified
characteristics:
The law of use and disuse " Body parts that are used a lot will become
well developed, and body parts that are not
used will shrink, and may eventually
disappear
" SNAKES with their vestigial pelvic bones
The law of inheritance of modified "Characteristics acquired by an organism in
characteristics: its lifetime are passed on to its offspring
"GIRAFFES and their long necks
, Today Lamarcks theory is rejected "Organisms do not evolve because they want
to
"These changes took place randomly, in
response to the environment
"There is very little evidence to support
Lamarcks hypothesis
THEORY 2: Darwinism "Those individuals who are BEST
ADAPTED to their environment, will be
able to BREED and produce offspring
"Over MANY GENERATIONS, beneficial
characteristics of the population will
dominate
"Changes in the environment drives the
selection of which characteristics will be
Observations that support NATURAL "Variation
SELECTION "Progeny (many are produced, but not all live
to adulthood)
"Competition (for limited resources)
"Genetics (characteristics that are shared)
-Natural selection (organisms with the most
advantageous characteristics are more likely
to survive and reproduce)
the theory of NATURAL SELECTION "Organisms produce a large number of
offspring
"Great amount of variation amongst the
offspring
"Some have favourable characteristics, and
some dont
"When there is a change in environmental
conditions, or competition&
"The organisms with characteristics more
suited will survive, and those that dont, will
die
"The organisms that survive, reproduce, and
pass the favourable characteristics on to
their offspring
"The next generation has a greater portion of
individuals with the favourable
Set Created By: Mrs V Oberholzer
" Hypothesis : Initial idea that needs to be tested BEFORE
it can be accepted as possibly true
" Theory Set of well-tested and widely accepted ideas
that explain something in science, and is
supported by A LOT of evidence
" So, HYPOTHESIS first, then TESTING, it may be accepted as a THEORY
if it is NOT DISPROVED
THEORY 1: Lamarckism Jean-Baptiste Lamarck
Believed that individual organisms had the
ability to change their appearance
AND, that these changes be present in their
offspring
Proposed 2 laws for species to evolve: " The law of use and disuse:
" The law of inheritance of modified
characteristics:
The law of use and disuse " Body parts that are used a lot will become
well developed, and body parts that are not
used will shrink, and may eventually
disappear
" SNAKES with their vestigial pelvic bones
The law of inheritance of modified "Characteristics acquired by an organism in
characteristics: its lifetime are passed on to its offspring
"GIRAFFES and their long necks
, Today Lamarcks theory is rejected "Organisms do not evolve because they want
to
"These changes took place randomly, in
response to the environment
"There is very little evidence to support
Lamarcks hypothesis
THEORY 2: Darwinism "Those individuals who are BEST
ADAPTED to their environment, will be
able to BREED and produce offspring
"Over MANY GENERATIONS, beneficial
characteristics of the population will
dominate
"Changes in the environment drives the
selection of which characteristics will be
Observations that support NATURAL "Variation
SELECTION "Progeny (many are produced, but not all live
to adulthood)
"Competition (for limited resources)
"Genetics (characteristics that are shared)
-Natural selection (organisms with the most
advantageous characteristics are more likely
to survive and reproduce)
the theory of NATURAL SELECTION "Organisms produce a large number of
offspring
"Great amount of variation amongst the
offspring
"Some have favourable characteristics, and
some dont
"When there is a change in environmental
conditions, or competition&
"The organisms with characteristics more
suited will survive, and those that dont, will
die
"The organisms that survive, reproduce, and
pass the favourable characteristics on to
their offspring
"The next generation has a greater portion of
individuals with the favourable
