BIOLOGY 1282 – LECTURE 2

• RECAP• INSTRUCTOR: ALIE PATRICK KOROMA• OFFICE: LIFE SCIENCE BLG RM 466• OFFICE HOURS: 11:30 a.m.-12:30 P.M

Monday and 12 noon to 2 P.M on Fridays• EMAIL: Koroma@exchange.uta.edu• 1282 web address: www.uta.edu/biology click on

syllabus and then 1282 for syllabus.• Powerpoints posted:

www.uta.edu/biology/alie/index.htm or

TODAYS MENU

• ADAPTATION –ADAPTIVE COLORATION

NATURAL SELECTION (Video)

• READ PAGES 15-19

• Assignment 1 due

• Assignment 2: Questions 1-10 (pg 23)

• Summary of Lab (1)

ADAPTIVE COLORATION

• Form and nature of color result of natural selection

• Types• 1. Cryptic Coloration a.k.a. camouflage• 2. Aposematic Coloration a.k.a warning

coloration• Flash Color a.k.a Startle coloration

The sand dab nightjar bird

Cryptic Coloration a.k.a. camouflage

A moth The leafy sea dragon

Florida treehopper insects

This cactus

Camouflage assists predators

a cheetah a frogfish

Warning coloration

The South American poison arrow frog

Chemical warfare

The bombardier beetle

A monarch caterpillar

Startle coloration

the false-eyed frog

The peacock mothcaterpillar larva of the swallowtail butterfly

ADAPTIVE COLORATION AND MIMICRY

• Types of Mimicry• 1. Batesian mimicry: resemblance to an

unplatable or venomous species (the model)• 2. Mullerian mimicry: all mimic species have

similar warning coloration. Are usually toxic or harmful

coral snake mountain king snake

monarch butterflyviceroy

Visual and behavioral mimicry

a jumping spiderthe snowberry fly

NATURAL SELECTION

THINGS TO WATCH FOR IN VIDEO

• Darwin• Evolution• Natural Selection• Species• Population• Adaptation• Fossils• Evidence of Evolution• Survival of the fittest

• Natural selection based on three conditions

• Natural selection acts on the population or species??

Natural selection and observations

• Natural selection is based on three observations/conditions

• 1. more young are produced than can survive• 2. variation exists between individuals• 3. The variation is inherited

How Does Natural Selection Work?

• Figure below: A flowchart of evolutionary reasoning

• Modern Genetics Confirmed Darwin’s Assumption of Inheritance

• Natural Selection Modifies Populations Over Time

•

Relatively constant resourcesand population size over time

Potential forrapid reproduction

Competition for survivaland reproduction

Variability instructures and behaviors

NATURAL SELECTION:On the average, the fittest

organisms leave the most offspring

Some variabilityis inherited

EVOLUTION:The genetic makeup of the population

changes over time,driven by natural selection

Observation

Conclusion based on observation

SUMMARY OF EVOLUTION

How Do We Know That Evolution Has Occurred?

• Fossils Provide Evidence of Evolutionary Change Over Time

• Comparative Anatomy Gives Evidence of Descent with Modification– Homologous Structures Provide Evidence

of Common Ancestry• Figure Homologous structures

Pterodactyl

Bird

Bat

Dolphin

Seal

Dog

Sheep Shrew

humerus

ulna

metacarpalsphalanges

radiuscarpals

Human

GRASPINGRUNNINGSWIMMINGFLYING

How Do We Know That Evolution Has Occurred?

– Functionless Structures Are Inherited from Ancestors

• Figure Vestigial structures

Salamander

Baleen whale

Boa constrictor

How Do We Know That Evolution Has Occurred?

– Some Anatomical Similarities Result from Evolution in Similar Environments

• Figure Analogous structures

How Do We Know That Evolution Has Occurred?

• Embryological Similarity Suggests Common Ancestry– Figure Embryological stages reveal

evolutionary relationships

Embryological stages reveal evolutionary relationships

lemur pig human

How Do We Know That Evolution Has Occurred?

• Modern Biochemical and Genetic Analyses Reveal Relatedness Among Diverse Organisms

What Is the Evidence That Populations Evolve by Natural

Selection?

• Evolution by Natural Selection Occurs Today– When Fewer Predators Are Present, Brighter Coloration

Can Evolve– Natural Selection Can Lead to Pesticide Resistance– Experiments Can Demonstrate Natural Selection– Selection Acts on Random Variation to Favor the Traits

That Work Best in Particular Environments

• Controlled Breeding Modifies Organisms

KEY WORDS

• Batesian and Mullerian Mimicry

• Adaptive Coloration-Types

• Adaptation• Fossils• Evidence of Evolution• Darwin• Evolution• Natural Selection

• Species• Natural selection based

on three conditions• Natural selection acts

on the population or species??

LAB

• Lab Exercise 1 pg 16-18.• The data should be graphed using a

spreadsheet. (Line Graph)• Write a short report on the lab. The following

format to be used: Title; Hypothesis/Purpose; Results; Conclusions.

• Summary Report and Assignment due next class.

Summary

• Title: has to be appropriate (4 points)• Hypothesis (2 points)

– The frequency of the allele/individual that is most adaptive will increase in the population and eventually become dominant

• Results: (2 points for explanation, 2 points for tables & 4 points for graph)

– Include two tables and a two graphs (Refer to example in class).

– Explain your table and graph in words to show the trends or numbers obtained

– Frequency is calculated as number of individuals of a particular group divided by total population

•

Summary Cont

• Discussion/Conclusion: (6 points: 2 points reject/accept hypothesis and 4 points explanation) – Reject and accept your hypothesis based on your

results– Explain your results. How do they fit with your

knowledge about your idea about how adaptive coloration affects predation rate.

– Think about the idea that populations and not individuals evolve. Also the prey with the color that is most adaptive will be hard to see and catch by the predator therefore survives and breeds.

– Draw conclusion