Taxonomy and Evolution



Intro to Taxonomy and Dichotomous Keys

Crash Course on Taxonomy

MyBrainShark- Taxonomy and Evolution


- The practice of classifying and naming things based on their ________. Not the same as taxidermy!

History of taxonomy:

Aristotle- named things based on things like ability to lay _______ or produce seeds

Others based groups on how they moved. But that would put birds closer to butterflies than ________!

Carolus Linnaeus is the _________ of taxonomy. He came up with the idea of naming and classifying things that we still use today.


Modern classification System

Based on Physical and Evolutionary relationships between organisms such as:

  • molecular comparisons
  • _____________ distributions
  • embryological data
  • _____________ patterns
  • ___________ comparisons

Kingdom, Phylum, Class, Order, Family, Genus and Species- __________ to most ___________

  • "King Phillip Came Over for Good ________"
  • "King Phillip's Children Ordered ________, Gravy, and Shakes"

Note: Linnaeus only went as far as including the Kingdom, Genus and Species of an organism.

Domain is a new classification above Kingdom.

  • ______ King Phillip Come Over for Good ______________?
  • ______ King Phillip's Children Order ________, Gravy, and Shakes?

Binomial nomenclature

Scientific name of each organism includes its _________ and species

Species- a group of organisms capable of interbreeding and producing _________ offspring.


Dichotomous Keys

Tools to help in the _______________ of organisms. Each object is named by using a flow chart that splits into _________ choices at each cross road.

How Can Paper Objects Be Grouped Lab

MyBrainShark- Dichotomous Keys, Binomial Nomenclature

Shark (and Monster) Key Lab
Binomial Nomenclature For Monsters
New York State Fish Key Lab



Spectacular Wildlife Photos

Natural Selection

Crash Course on Natural Selection

Charles Darwin proposed that natural selection (organisms with ____________ traits survive environmental change) is the mechanism that causes species to __________ over time.

He discovered this by studying finch ______ in the Galapagos Islands. The birds on different islands adapted by developing different ________ to eat the local food.

The basic principles in natural selection are:

1. Different members of the same species have a variety of genes (due to _________ and ________ shuffling)
2. Species create A LOT more offspring than can _________ and each family's young is full of ___________.
3. Limited resources create competition- "The ___________ for Survival".
4. Organisms with favorable variations survive and _____________ OR the species ______ out.

Organisms that are better adapted to their environment and able to reproduce successfully are considered “_______”.

  • Being "____" simply means that the organism will create offspring
  • Evolutionary fitness has nothing to do with ___________ fitness. __________ is not always better.

Unfit organisms die, and their traits are eventually ____________ from the ________ pool.

Castle Learning: Natural Selection

Beaks of Finches Lab


Crash Course on Speciation

Evolution is usually driven by:

  • changes in __________
  • __________
  • competition for ________
  • geographic isolation

Geographic isolation can lead to ____________ isolation (a new species)

To evolve, variations must exist in a species _____________ the environment changes. They do not get a trait just because it is ___________.

_______________ misunderstood and thought that the ___________ of an organism created a change in the organism!



Crash Course on Evolution

Evidence in support of evolution comes from:

  • ________ records- preserved specimens in sedimentary rock record evolutionary history
  • radioactive dating- the ______ life of an element can give us its age
  • ___________- the DNA of an organisms indicates its relation to other organisms
  • anatomy- our history is recorded in our ________ structure
  • embryology - the ___________ of embryos follow evolutionary changes

Comparative anatomy - By comparing ________ and organs of ___________ species we can determine a LOT about their evolutionary relationships.

  • Homologous- animals that share the ________ structures indicating the _______ common ancestral origin ex. bat wing and human arm
  • Analogous- animals that share the ________ structure but _________ the same common ancestral origin ex. insect wing and bird wing
  • Vestigial- useless structures that DID have a function until evolution _________ the animal to ___ longer need it

Evidence of Evolution Lab

Castle Learning: Evolution Evidence

Evolutionary Development

Crash Course on Evolutionary Development

MyBrainShark- Change is Inevitable

Modern species evolved from an earlier, different species which shared a _________ ancestor (long, long ago they had the same mom). ex. fox and wolves and _______

The more similar two organisms are the more ___________ they evolved in different directions.

  • Chimpanzes are ____ % the same genetically as humans- that's a "recent" split_
  • Mice have ____ % of the same genes as humans- we evolved in different directions from mice way back in evolutionary history

Gradualism is a theory that says evolution occurs ________.

Punctuated equilibrium is a theory that says evolution happens in quick ________.

Cladograms show common ancestory.

Reconstructing the Evolutionary History of Biological Diversity Lab

More than Birds- a cappella answer to how reptiles evolved into birds

Evo-Devo- How we get from single cells to people

  • gene regulatory networks and inscription factors