Transcript coloration - mcdowellscience

Special Adaptations and Speciation
-What are some specific ways that
organisms have adapted to their
environment?
-An adaptation is a trait that an
organism has that allows them to be
more fit for their environment.
Ex: use less water, larger eyes
Adaptations have evolved over huge
amounts of time, in response to the
pressure put on an organism from the
environment.
If the environment changes, the traits
that best fit the new environment will
be advantageous.
Evolution of Adaptations Observed
Industrial Melanism is an evolution
in coloration caused by a change in
the environment.
The color of the trees went from a light
gray to a dark gray/black fairly rapidly.
Peppered moths had a natural variation
in color, from light gray to black.
There were always a few moths with different
colors.
Prior to the change, the advantage was
for the light colored moth.
After the change, the advantage was
for the dark colored moth.
Explain how the change in environment
caused Industrial Melanism in the Peppered
Moth, and why the change was possible.
What would happen to the population of
moths if the trees were to turn light gray
again?
Why was variation within the population
so vital to the evolution of the moth?
Did individual moths change their color?
Camouflage and Other Tricks
Camouflage is the adaptation of
having coloration that blends in with
the surrounding environment, making
the organism less likely to be eaten, or
allowing the organism to approach
prey without being seen.
JUST LIKE THIS!!!
What do
You see
in the
picture?
This praying mantis has a coloration
called cryptic coloration.
It allows the mantis to hide on branches,
and not be eaten, as well as to sneak
up on unsuspecting prey.
The coloration in this
case is both for defense
and offense.
This organism is
called the Twig
Caterpillar.
It has cryptic
coloration to allow
it to blend in with
the tree branch.
This is an example of
a Katydid, which is
hidden because it
resembles a leaf.
In this case, the coloration is defensive,
because Katydids are not predatory.
What do you think happens to this Katydid in
the Fall of the year, when leaves turn color?
Countershading
• LOOKS LIKE THIS ON TOP
• LOOKS LIKE THIS ON BOTTOM
• A type of camouflage in which the top (dorsal)
side of an organism is darker than the bottom
(ventral) side
• Reduces shadow effects which give visual cues
to the animal
• Also works through background matching
Grey Squirrel
Emperor Penguins
Warning coloration is a display shown by
organisms that announce rather than hide
by their coloration.
Often, these organisms taste bad, or have
a sting.
Predators learn to shy away based on
their appearance.
Yellow Jacket (Wasp)
Striped Skunk
This is a
Nudibranch,
a marine mollusk.
Why do you think it
would it advertise
itself this way?
It is brightly colored to advertise the
fact that it tastes bad.
This is the
Foaming
Grasshopper,
From the
Rainforest of
South America
Do you think its coloration is designed to
hide or advertise? Why?
This is the
Scorpion Fish
What is the
name of the
type of
coloration it has?
Why is it an
adaptive advantage to have this coloration?
This is a Tropical
Katydid.
What type of
coloration does
it have?
Is this coloration for
defense or offense?
Mimicry is a deceptive form of camouflage.
It works because one organism that is harmless
takes the warning coloration of another
organism that either tastes bad or has some
defensive mechanism, such as a sting.
The harmless, tasty organism is called the
mimic.
The original organism with the warning
coloration is the model.
The Viceroy
butterfly (L),
mimics the Monarch
butterfly ( R),
because the Monarch
tastes bad.
Which butterfly is the mimic,
and which is the model?
King Vs. Coral Snakes
These two frogs are
distinct species, but
closely resemble
each other.
One is a mimic, the
other is the model.
Why do you think one
Frog is mimicking the
other?
Several different
Species of African
butterfly.
What type of coloration
do they exhibit?
Which do you think
are the Mimics?
What are the other
ones called?
Mimicry of Body Parts
(Eyespots)
Click Beetle Eyespots
Display Coloration
• LOOKS LIKE: whatever is attractive to the
particular species
• Coloration and/or structures used by one
gender of a species to attract mates of the same
species
• Usually the male attracting the female
• Coloration often related to important aspects of
the species’ survival
Caribbean Flamingo
• Baby flamingoes are
grey or white
• Pink color comes from
beta-carotene in shrimp
that it eats
• Females attracted to
“pinker” males;
indication of health
Ruby-throated Hummingbird
Peacock vs. Peahen
Magnificent Frigatebird: Which
Coloration?
The End
Why
me,
LORD
?
Other Types of Adaptations
-Adaptations take many forms, and have 3
main types.
1) Morphological Adaptation: involve the
structure of an organism.
Ex: Beaks of birds, large eyes in nocturnal
animals, flippers on seals
Can you think of any more?
2) Physiological Adaptations:
Involved with the functions of an
organism.
Ex: being able to digest a certain food,
having different enzymes, tolerance
to salt, less need for oxygen.
What other types can you think of?
3) Behavioral Adaptations:
These involve an organisms reaction
to its environment.
Ex: migration, storing food,
timing of breeding.
What type of adaptation do you think
Hibernation is?
Evolving to New Species
New species evolve because the
environment changes, and the
organisms have to adapt to the new
conditions, or go extinct.
Sometimes a founder species (the
original form) is broken into two or
more parts, and kept separate.
If the parts of the old species cannot
communicate and interact, they
are said to be Geographically Isolated.
Ex: Various unique species on islands,
Such as Madagascar, Hawaii, and
Australia
Can you think of another way species could
be isolated, other than being on an island?
Geographic Isolation leads to Reproductive
Isolation, where, eventually, the two groups
will no longer be able to breed.
They will have become two distinct
species.
This is called divergence, which means
“heading in different directions”.
Can you think of any examples
of divergence?
Geographic Isolation
Differential Evolution over time
Reproductive Isolation
The Galapagos Finches are a classic
example of geographic isolation leading
to speciation, the development of new
distinct species.
The original finches were separated
onto the various islands when they
formed,and because of distance,
were kept apart.
The environment of each island was
slightly different, so the finches had to
adapt differently on each island.
Eventually, over long periods of time,
they evolved into completely different
species, each adapted to its conditions.