RTW Friday, January 31 st What is your definition for evolution?

RTW Friday, January 31st

What is your definition for evolution?

Today’s Agenda

Recommendations for 2014-15 Anatomy/Physiology Anatomy/Physiology Honors Biology II Environmental Science Marine Science

Test corrections Start vocabulary

Evolution Vocabulary

Endosymbiotic Theory

Evolution Convergent Evolution Coevolution Punctuated

Equilibrium Descendant Ancestor Fossil

Homogolous Sturcture

Vestigial Structure Analogous

Structure Embryology Biogeography Hominid Candidate Fossils

RTW Monday, February 3rd

What came first, the chicken or the egg?

ORIGINS OF LIFE

Theories of the Origin of Life Abiogenesis

Primordial soup Endosymbiotic theory Hydrothermal vents Panspermia

Abiogenesis

= "non biological origins“: hypothetical generation of life from non-living matter.

Spontaneous generation

Primordial Soup

Famous Miller-Urey experiment (1953) suggested that lightning might have helped create the key building blocks of life on Earth in its early days. Over millions of years,

larger and more complex molecules could form.

Electric sparks can generate amino acids and sugars from an atmosphere loaded with water, methane, ammonia and hydrogen.

Endosymbiosis

Deep-Sea Vents

The deep-sea vent theory suggests that life may have begun at submarine hydrothermal vents

These vents spew key hydrogen-rich molecules. Their rocky nooks could then have concentrated these molecules together and provided mineral catalysts for critical reactions.

Even now, these vents, rich in chemical and thermal energy, sustain vibrant ecosystems.

Panspermia

= life did not begin on Earth at all, but was brought here from elsewhere in space

Rocks regularly get blasted off Mars by cosmic impacts, and a number of Martian meteorites have been found on Earth that some researchers have controversially suggested brought microbes over here, potentially making us all Martians originally.

“Happy Birthday Earth!”

How old are you? The Earth is 4.6 BILLION years old!

In this activity…You will be designing a geological birthday card for the Earth for a specific time period.

To do this you will need to calculate your “Geological Birthday”…

Calculating Your Geological Birthday

1.) Divide the age of the Earth by the number of days in a year.

2.) Next add the number of days from the beginning of the year until your birthday.

3.) Subtract this number of days from the total number of days in a year.

4.) Figure out the equivalent number of years on the geological time scale.

5.) Round to the nearest million years.

Month # of Days

January 31

February 28

March 31

April 30

May 31

June 30

July 31

August 31

September

30

October 31

November 30

December 31

Example Birthday: September 5th

1.) 4.6 billion/365 = 12,602,740 years per day 2.) 31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 5

= 248 days 3.) 365 - 248 = 117 At the end of the year my

birthday was 117 days ago 4.) (12,602,740 years/day) x (117 days) =

1,474,520,580 years 5.) 1,474,520,580 rounds to 1,500,000,000

which can also be expressed as 1,500 MYA or the Metoproterozoic

Now what?

Design a birthday card for the Earth at that time

Your card should convey something about that time period. Environment Presence or absence of life Arrangement of continents Anything else you learned about that time

http://www.ucmp.berkeley.edu/help/timeform.php

RTW Tuesday, February 4th

What is one theory of the origins of life that we discussed yesterday and what does it entail?

Evidence for Evolution Project You will be placed into groups of 6 Each group will have specialists:

Anatomist- study the structure of organisms Physiologist- study the function of

organisms Paleontologist- study fossils Molecular biologist- study genetics

Within your group you need to have 2 of the same specialists (one specialist will not be represented)

Evidence for Evolution Project With your role you will research 4-5

examples of evidence for evolution Find specific examples, so when you

present to the class you will have different examples to share (also find the dates when the evidence was discovered)

To start your research: Google “Evidence for evolution webquest” Scroll down and utilize the links for your role

Evidence for Evolution Project As a group you are creating a poster that

will be presented (“Evidence for evolution webquest”)

Organize your information in a chart:Evidence for Evolution

Special Areas of Interest

Evidence (descriptions or

drawings)

Significance

Anatomy

Molecular Biology

Paleontology

RTW Wednesday, February 5th

What is one piece of evidence for evolution (think about what you

researched yesterday)?

RTW Thursday, February 6th

How does this picture provide support for the theory of evolution?

RTW Friday, February 7th

What is a vestigial structure and what is an example of one?

HAPPY FRIDAY!

Key Concept

Evidence of common ancestry among species comes from many sources.

Evidence for evolution came from several sources. Fossils provide evidence of evolution.

Fossils in older layers are more primitive than those in the upper layers.

Paleontology provides evidence to support evolution.

The study of geography provides evidence of evolution. Island species most closely resemble nearest

mainland species Populations can show variation from one

island to another

Embryology provides evidence of evolution. Identical larvae, different adult body forms Similar embryos, diverse organisms

The study of anatomy provides evidence of evolution. Homologous structures are similar in

structure but different in function. Homologous structures are evidence of a

common ancestor.Human hand Bat wingMole foot

Human hand

Bat wing

Mole foot

Fly wing

The study of anatomy provides evidence of evolution. Analogous structures have a similar

function. Analogous structures are NOT evidence

of a common ancestor.

Structural patterns are clues to the history of a species

• Vestigial structures are remnants of organs or structures that had a function in an early ancestor.

• Ostrich wings are examples of vestigial structures.

Molecular & genetic evidence support fossil & anatomical evidence

Two closely-related organisms will have similar DNA sequences.

Humans share a common ancestor with other primates. Primates are mammals with flexible

hands and feet, forward-looking eyes and enlarged brains.

Anthropoids are humanlike primates.

So why are humans so advanced?

BRAINSTORM with a shoulder partner about what makes us more advanced than other primates and organisms

So why are humans so advanced? Bipedal means walking on two legs.

– foraging– carrying infants and food– using tools

HUGE brains! Language Use of tools

Article Review

Read the article. Write down the answers in your

notebook (part of the notebook check). When done, turn to your shoulder

partner and summarize your article.

RTW Monday, February 10th

A. They are offspring are

from a common parentB. They have a distant

common ancestorC. They developed in the

same locationD. They evolved into the

same species

Based on embryology & developmental patterns, what can you infer from this diagram?

NATURAL SELECTION

Or, how did we get here….

Natural Selection

Natural selection is a mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals.• Heritability is the ability of a trait to be

passed down.• There is a struggle for survival due to

overpopulation and limited resources.• Darwin proposed that adaptations arose over

many generations.

• There are four main principles to the theory of natural selection.– variation

Natural selection explains how evolution can occur.

– overproduction– adaptation– descent with modification

VARIATIONOVERPRODUCTIONADAPTATIONDESCENT withMODIFICATION

Variation

1. Reproduction occurs with variation This variation is heritable (traits inherited

from parents)

Variation

Variation is a difference in a physical trait. Galápagos tortoises that live in areas with

tall plants have long necks and legs. Galápagos finches that live in areas with

hard-shelled nuts have strong beaks.

Overproduction

2. Overproduction of offspring (too many babies!)

There is competition among living things More are born or hatched or whatever, than

survive and reproduce

Adaptations

3. An adaptation is a feature that allow an organism to better survive in its environment.– Species are able to adapt to

their environment.– Adaptations can lead to

genetic change in a population.

Descent with Modification

4. Selection determines which individuals enter the adult breeding population

This selection is done by the environment Those which are best suited reproduce They pass these well suited characteristics

on to their young Fitness describes how reproductively

successful an organism is in its environment.

This lecture keeps evolving….. Survival of the Fittest means those who

have the most offspring that reproduce ‘Descent with modification from a

common ancestor, NOT random modification, but, modification shaped by natural selection’

• Natural selection can act only on traits that already exist.• Structures take on new functions in addition to their

original function.

Natural selection acts on existing variation.

wrist bone

five digits

Other Evolutionary Theories

Lamarckism Inheritance of acquired characteristics

E.g., giraffes really wanted leaves, so they stretched their necks and…..

‘Cave dwelling fish don’t use their eyes so they disappear’

‘We don’t use our appendix so it is disappearing’

RTW Tuesday, February 11th

Explain why some animals have more or fewer offspring at a time. Which do you think is the better strategy?

Mechanisms of Change

Gene Flow Migration & Emigration

Genetic Drift Bottleneck Effect Founder Effect Speciation

Non-random mating Sexual Selection

Genetic Recombination

Gene flow is the movement of alleles between populations.

Gene flow occurs when

individuals join new populations and reproduce.

keeps neighboring populations similar.

Low gene flow increases the chance that two populations will evolve into different species.

bald eagle migration

Migration & Emigration

Gene flow moves alleles from one population to another.

Genetic drift is a change in allele frequencies due to chance. Genetic drift causes a loss of genetic

diversity. It is most common in small populations. A population bottleneck can lead to genetic

drift. It occurs when an event

drastically reducespopulation size.

The bottleneck effect isgenetic drift that occursafter a bottleneck event.

Genetic Drift

Genetic drift has negative effects on a population.

– less likely to have some individuals that can adapt – harmful alleles can become more common due to

chance– Genetic drift changes allele frequencies due to

chance alone.

Founder effect

The founding of a small population can lead to genetic drift.

– It occurs when a few individuals start a new population.

– The founder effect is genetic drift that occurs after start of new population.

Sexual selection occurs when certain traits increase mating success.

Sexual selection occurs due to higher cost of reproduction for females. males produce many

sperm continuously females are more

limited in potential offspring each cycle

Sexual selection selects for traits that improve mating success.

Types of Sexual Selection

There are two types of sexual selection.

– intrasexual selection: competition among males

– intersexual selection: males display certain traits to females

Genetic Recombination

Mutations produce the genetic variation needed for evolution.

Exit Slip

There are many different species of birds, but they all have different songs. Explain what kind of mechanism of change this

is and how it works.

Vocab

Evolution Natural selection Variation Fitness Adaptation Descendant Vestigal structure Homologous structure Analogous structure

RTW Wednesday, February 12th

Write down an example of an animal that has adapted to survive in its environment.

Ipad Activity

Google “Natural Selection Examples” and click first option (Discovery Channel)

Pick five examples For each example, answer the following

IN YOUR NOTEBOOK:1. Name of species2. Describe the trait being selected.3. How does the trait help the organism

survive in its environment?

Peppered Moths

An example of evolution of a species over the past 200 years

Before the Industrial Revolution in England the trees were a mottled white color.

Coal burning factories began producing soot that covered the forests, making the trees black in color.

The peppered moth population responded to this change, by adapting to their environment

Moth Activity

Instructions

You will be given a moth outline Cut it out Color it (AT LEAST 2 COLORS) Camouflage the moth for a specific

surface around the room