Patterns of Evolution

Patterns of Evolution

Coevolution Two or more species that interact may evolve

together. Examples:

Predator-prey Parasites and hosts Plants and their pollinators

Convergent Evolution

Organisms that appear to be very similar, are not closely related at all.

The environment selects for the phenotype Examples:

Sharks and Dolphins

Analogous structures are associated with convergent evolution

Divergent Evolution When closely related species become

more dissimilar usually because of different habitats

Adaptive radiation: related species evolve from a single ancestral species

Things that effect evolution change in climate/habitat: a trait that

was an advantage may no longer be an advantage

genetic drift: change in allele frequency by chance

events greater impact on small populations

migration: species can be seperated or exposed to new environments

geographic isolation: a species can be seperated geographically (canyon, different islands, etc.)

mutations: new variations can arise by random chance

reproductive isolation: something prevents organisms from sucessfully breeding examples: different mating seasons, different mating calls

Classification Taxonomy: the branch of biology that

names and groups organism according to their characteristics and evolutionary history.

Aristotle was the first to use this method but was replaced due to confusion

Carolus Linnaeus (1707-1778) Swedish Naturalist Devised a system of grouping organisms

into categories based upon form and structure

Created seven different levels of organization

7 Levels of Classification Kingdom Phylum Class Order Family Genus Species

Kindly Pass Connie Over Fresh Green Salad

Binomial Nomenclature

Two Name Naming System

Binomial Nomenclature System that gives organisms two-part

scientific name Genus species Genus is capitalized and both are in

italics

Examples: Homo sapiens Lynx rufus

3 Domain System Recently, scientists have added a group

above Kingdom.  Three groups, called DOMAINS.

Domain Eukarya - includes organisms composed of eukaryotic cells (plants, animals, fungi, protists)

Domain Bacteria - includes all prokaryotic cells, Kingdom Eubacteria

Domain Archaea - includes only "ancient" bacteria, Archaebacteria

Tree of life Phylogenetic Tree:

showing evolutionary relationships among various species based upon similarities and differences in their physical and/or genetic characteristics.

Phylogenetic Trees Use a combination of:

Shared anatomical structures Pattern of embryological development Types of proteins DNA sequencing

Node

Derived Character: Characteristics that appear more recently in a group but are not seen in older organisms

Closely Related

1. ______ Wings2. ______ 6 Legs3. ______ Segmented Body4. ______ Double set of wings5. ______ Jumping Legs6. ______ Crushing mouthparts7. ______ Legs8. ______ Curly Antennae

Dichotomous Keys A step-by-step guide to help identify an

organism Follows a series of choices that lead you

to the organism’s name

Dichotomous Keys

1. Has green colored body ......go to 2

Has purple colored body ..... go to 4

2. Has 4 legs .....go to 3

Has 8 legs .......... Deerus octagis

3. Has a tail ........ Deerus pestis

Does not have a tail ..... Deerus magnus

4. Has a pointy hump ...... Deerus humpis

Does not have a pointy hump.....go to 5

5. Has ears .........Deerus purplinis

  Does not have ears ......Deerus deafus

answersA. Deerus magnusB. Deerus pestisC. Deerus octagisD. Deerus purplinisE. Deerus deafusF. Deerus humpis