Unit 7b - Evolution

The Tree of Life

Taxonomy

Taxonomy is the science of classifying and naming organisms.

Based on shared physical characteristics.

Invented by Carolus Linnaeus in the 18th century.

His real name was Carl von Linne…

Binomial Nomenclature

Binomial Nomenclature - each organism has a Latin two-word name consisting of its genus and species.

The genus is always capitalized. If you type a name, it is in

italics – Homo sapiens If handwritten, it is underlined

– Homo sapiens

Linnaeus’s 7 Groups

1. Kingdom – the most general group.

2. Phylum

3. Class

4. Order

5. Family

6. Genus

7. Species – the most specific group.

“King Phillip Came Over For Great Sushi.”

The 6 Kingdoms

1. Animals – includes microscopic animals, shellfish, and humans

2. Plants – mosses, ferns, and trees

3. Fungi – mushrooms, yeast, and mold

4. Protista – amoeba, euglena, and algae

5. Eubacteria – “true bacteria” with over 10,000 species; some are helpful, some are harmful.

6. Archaebacteria – “ancient bacteria” with only a few hundred species; most live in harsh environments like seawater, hyrdrothermal vents, and swamps.

How do you break up the kingdoms?

Number of Cells - Single celled or multi-celled.

Cell Type - Prokaryotes or eukaryotes. (Does it have a true nucleus or not?)

Nutrition - Autotroph or heterotroph (Does it make its own food through photosynthesis/ chemosynthesis or not?)

Using a Dichotomous Key

A dichotomous key is a series of paired “either/or” statements based on observable traits.

Dichotomous Key to Represented Birds1 a. The beak is relatively long and slender Certhidea b. The beak is relatively stout and heavy Go to 22 a. The bottom surface of the lower beak is flat and straight Geospiza b. The bottom surface of the lower beak is curved Go to 33 a. The lower edge of the upper beak has a distinct bend Camarhynchus b. The lower edge of the upper beak is mostly flat Platyspiza

Adaptive Radiation and Convergent Evolution

Adaptive Radiation – a common ancestor divides into multiple species over a long period of time. (Ex: Galapagos finches)

Similar Different Convergent Evolution – different species

living in a similar environment evolve to have similar features. (Ex: whales and fish)

Different Similar

Co-Evolution

Coevolution - When two species evolve together and need each other for survival.

Symbiosis – any relationship where two organisms of different species live closely and interact.

Niche - An ecological niche is the role and position a species has in its environment - how it meets its needs for food and shelter, how it survives, and how it reproduces. A species' niche includes all of its interactions with the biotic and abiotic factors of its environment.

Relationships in Ecosystems

There are 5 kinds of relationships and 3 kinds of symbiosis (#1-3):

1.Mutualism – two species, both benefit (+,+).

2.Commensalism – two species, one benefits and the other isn’t helped or harmed (+,0).

3.Parasitism - a species harms another/lives off of it without killing it (+,-).

4.Predation - one species eats another (+, -)

5.Competition - one species; individuals compete to survive (-,-). Speciation can occur.

Cladograms

Cladogram – a diagram that shows the evolutionary relationship between organisms.

Uses primitive and derived traits to make groups.