Transcript Changes Over Time

Created by: Mrs. Herman 2012
Fossils are remains or evidence of once-living organisms.
FOSSIL FORMATION
BrainPop Video: Textbook, Chapter 6, lesson 1 resources. http://connected.mcgrawhill.com/media/repository/protected_content/COMPOUND/50000016/12/60/Fossils/00076703.htm?stateCode=FL
The Fossil
Record is
made up
of all the
fossils ever
discovered
on Earth.
 What is the estimate age of the
trilobite fossils (bottom layer of
fossils)?
 Which layer is approximately 460
million years old?
Index fossils
Index fossils are fossils
that can be used to date
the rock in which they are
found. The best examples
are fossils of animals or
plants that lived for a very
short period of time and
were found in a lot of
places. Ammonites,
shelled relatives of today’s
octopus, make ideal index
fossils.
Library of Congress, Prints and
Photographs Division [reproduction
number, e.g., LC-USZ61-104].
 Born in England, 1809
 Studied Medicine at
Edinburgh University
 Transferred to Cambridge
University
 Studied to be a Minister
http://www.pbs.org/wgbh/evolution/library/11/2/quicktime/e_s_2.html
 Hired as Naturalist on H.M.S. Beagle
 Sailed on Five Year Scientific Expedition
 Down East Coast of South America
 Up Pacific Coast to Galapagos Islands
 Made Stops on Mainland and Islands
 Observed Variety of Life and Habitats
The Galapagos Island
 The smallest, lowest islands were hot, dry, and nearly barren-Hood
Island-sparse vegetation
 The higher islands had greater rainfall and a different assortment of
plants and animals-Isabela- Island had rich vegetation.
The Galapagos Island
 Darwin was fascinated in particular by the land tortoises and marine iguanas in the Galápagos.
 Giant tortoises varied in predictable ways from one island to another.
 The shape of a tortoise's shell could be used to identify which island a particular tortoise inhabited.
 Proposed Evolution Resulting from
Natural Selection:
Organisms Produce Many Offspring
Competition for Food, Territory, Mates,
etc.
Those With Best Traits Survive
Organisms Change Over Many
Generations
 Time Frame: Millions of Years
Evolution by Natural Selection
From: Evolution and the Fossil Record By John Pojota Jr. and Dale A. Springer
 Variations exists among individuals within a species.
 Organisms produce more offspring than the environment can
support.
 Competition exists among individuals
 The organisms whose variations best fit them to the
environment are the ones who are most likely to survive,
reproduce and pass these desired variations on to the next
generation. (survival of the fittest)
http://learn.genetics.utah.edu/content/variation/recipe/
Natural
Selection
Over time, natural
selection results in
changes in inherited
characteristics of a
population. These
changes increase a
species fitness in its
environment
toad
Animal
Adaptations
Adapted from: Ms. Weinberg
Have you ever wondered how animals are able to survive in the
wild?
Animals have certain adaptations that help them to survive.
Think about the way you dress in the winter.
You don’t wear your shorts and bathing suit when it’s snowing
outside!
You wear warm clothes, and maybe
even a hat and mittens to protect
yourself from the weather.
And what if you are having a snowball fight?
You probably run away from the person
throwing at you, and maybe even try to sneak
up on that person and throw some snowballs!
The way you dress in the winter, as well as the way that you run and
hide from someone throwing snow at you are kinds of …
Adaptations
An adaptation is an inherited trait that increases an organism’s
change of surviving and reproducing in its environment.
We can separate adaptations into two
categories:
Physical
A
D
(structural and
functional)
A
P
T
AND
A
T
I
O
N
S
Behavioral
Physical adaptations
are body structures that allow an
animal to find and consume food,
defend itself, and to reproduce its
species.
Physical adaptations
help an animal survive in
its environment.
© A. Weinberg
Physical adaptation
Camouflage (use of color in a surrounding)
The chameleon can change its color to match its
surroundings.
Physical adaptation
Mimicry
(looking or sounding like another living organism)
The Viceroy butterfly uses mimicry to look like the Monarch
butterfly. Can you tell them apart?
I’m the
Viceroy!
Not poisonous
Poisonous
I’m the
Monarch!
Physical adaptation
Chemical defenses (like venom, ink, sprays)
Physical adaptations
Body coverings & parts (claws, beaks, feet, armor plates, skulls,
teeth)
The elephant’s trunk is a physical adaptation that helps it to clean
itself, eat, drink, and to pick things up.
Now let’s learn about
Behavioral Adaptations…
Behavioral Adaptations allow animals to
respond to life needs.
Behavioral Adaptations
are animals’ actions.
Remember that Physical Adaptations are body
structures.
Each organism has unique methods of
adapting to its environment by means of
different actions.
We can divide Behavioral Adaptations into two groups:
Instinctive
Learned
These behaviors
happen naturally &
don’t have to be
learned.
These behaviors
must be taught.
Instinctive
behaviors
Methods of gathering &
storing food
Finding shelter
happen naturally & don’t
need to be learned
=
Defending oneself
Raising young
Hibernating
Migrating
Learned
behaviors
=
Obtained by interacting with
the environment and cannot
be passed on to the next
generation except by
teaching.
Changes…..
Environments are complex. Species must adapt to an
environment’s living parts as well as it’s nonliving parts.
Nonliving parts include temperature, water, nutrients in soil
and climate. Deciduous trees shed their leaves due to changes
in climate. Camouflage, mimicry and mouth shape are
adaptations mostly to an environments living parts.
Living and nonliving factors are always changing. Even slight
environmental changes affect how species adapt. If a species is
unable to adapt, it becomes extinct. The fossil record contains
many fossils of species that were unable to adapt to change.
From text page 222
 Biological Evolution - the change
over time in populations of related
organisms.
 Extinction – occurs when the last
individual organism of a species dies.
Evidence of Evolution
 The Fossil Record
 Geographic
Distribution of Living
Things
 Homologous Body
Structures
 Similarities in Early
Development
Evidence of Evolution
 The Fossil Record
 Geographic
Distribution of Living
Things
 Homologous Body
Structures
 Similarities in Early
Development
Evidence of Evolution
 The Fossil Record
 Geographic
Distribution of Living
Things
 Homologous Body
Structures - structures
that have different
mature forms in different
organisms, but develop
from the same
embryonic tissue
 Similarities in Early
Development
Evidence of Evolution
 The Fossil Record
 Geographic
Distribution of Living
Things
 Homologous Body
Structures
 Similarities in Early
Development
Evidence of Evolution
 The Fossil Record
 Geographic
Distribution of Living
Things
Rib cage of a Python
Vestigial organs - organs
that serve no useful
function in an organism,
i.e. appendix, tail bone.
 Homologous Body
Structures
 Similarities in Early
Development