Phenology Friday

Bloodroot (Sanguinaria canadensis) What it is? Perennial, herbaceous flowering plant native to eastern North America that is in bloom right now. What is unique about this plant? It’s root sap is red and poisonous and it’s seeds are dispersed by ants. What are its uses? It’s a popular red natural dye used by Native American artists and it is also found in some dental hygiene products.

Drill # 5 4/4/14 How can you use Darwin’s theory of evolution to explain the following: Bloodroot’s red, poisonous root sap Bloodroot’s relationship with ants The seeds have a fleshy part that attract ants. The ants take the seeds to their nest, where they eat the elaiosomes, and put the seeds in their nest debris, where they are protected until they germinate. They also get the added bonus of growing in a medium made richer by the ant nest debris. All parts of the plant are poisonous to animals but the toxins are most highly concentrated in the root after leaves are completely open.

SWBAT: Use the fossil record to determine the relative age of an organism. Use comparative anatomy to determine if species share a common ancestor. Describe how to use embryology to determine which species have the more recent common ancestor. Determine evolutionary relationships by analyzing amino acids.

Agenda Extension from Peppered Moth Lab Notes on the 4 Types of Evidence of Change including fossil records, comparative anatomy, embryology and amino acid analysis

Evolution 4 Types of Evidence of Change: 1. Fossil Records 2. Comparative Anatomy 3. Similarities in Embryology 4. Similarities in DNA, RNA and proteins

Fossil Records Fossils - the preserved remnants or impressions left by organisms that lived in the past. May bear a resemblance to organisms that exist today. Fossil record - the order in which fossils appear within sedimentary rocks. Shells, bones, teeth, etc.

Types of Fossils

Look at the rock cycle and define sedimentary rock in your notes.

Dating Fossils 1. Law of Superposition 2. Carbon-14 dating

Fossil record creates: Law of Superposition Fossil record creates: A geologic time scale Fossils at the bottom of the strata are older Fossils at the top of the strata are younger A relative age is determined based on fossil’s location within the sedimentary rock record

Carbon 14 Dating Age of a fossil is based on the amount of radioactive carbon that is in the sample (decays to Nitrogen 14)

Example of fossil record showing evolution

Homologous structures 2. Comparative Anatomy Homologous structures Structures may vary in function and appear different, but they all have common skeletal structures Indicates that the species share a common ancestor

As a general rule, the more homologous parts that two species share, the more closely related they are. Which two organisms have a closer common ancestor? Explain.

Comparative Anatomy Analogous structures Structures have identical function due to similar environmental pressures Do not necessarily have a common ancestor Wings in birds and insects

The more complex two structures are, the less likely that they evolved independently. Do the organisms below share a common ancestor? Explain why or why not.

Drill # 6 4/7/14 Describe the two types of evidence of evolution we have discussed so far. Define and give one example.

SWBAT: Describe how to use embryology to determine which species have the more recent common ancestor. Determine evolutionary relationships by analyzing amino acids.

Homework Due Peppered Moth Lab

Agenda Homework Finish notes on the 4 Types of Evidence of Change. Evolution Vocabulary WS Hand back Animal Fact Sheet Amino Acid Analysis (if time) Homework Complete Comparative Anatomy WS

Evolution 4 Types of Evidence of Change: 1. Fossil Records 2. Comparative Anatomy 3. Similarities in Embryology 4. Similarities in DNA, RNA and proteins

Comparative Anatomy Vestigial structures Indicates that the structure was functional in some ancestor of the organism Probably shares a common ancestor with an organism that has a functional version of the same feature Appendix in humans Pelvic bones in baleen whales

More similarities in embryos, the more recent the common ancestor 3. Similarities in Embryology Early stages of development of different embryos are very similar to each other More similarities in embryos, the more recent the common ancestor

Embryo Challenge Stage I: label each embryo Human Hog Calf Fish Tortoise Salamander Rabbit Chick

Embryo Challenge Stage II: label each embryo Human Hog Calf Fish Tortoise Salamander Rabbit Chick

Embryo Challenge Answers:

4. Similarities in DNA, RNA and proteins The more recently two species have branched from a common ancestor, the more similar their DNA and amino acid sequences.

Wrap up Darwin’s theory of evolution by natural selection explains changes in : A. individuals B. genetic makeup C. populations of species D. environment

Drill # 4 4/4/14 How do we know that animals and plants have evolved? What types of evidence can we see today?