Biology 101: Evolution and History of Life

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Questions and Answers

Which individual is responsible for the lecture content specifically covered during weeks 1-3 of the course?

Dr. Glasgow

Katie Hunter

Dr. Szuroczki (correct)

Dr. Martin

If a student misses a midterm test, which individual should they contact immediately?

Dr. Martin

Dr. Glasgow

Katie Hunter (correct)

Dr. Szuroczki

What percentage of the final course grade is attributed to laboratory assignments?

40%

35% (correct)

30%

25%

According to the topic schedule, which chapter primarily focuses on the 'History of Life on Earth'?

Chapters 26.1-26.2 (B) Signup and view all the answers

Which of the following is NOT a listed key concept under the introduction to evolution?

Origin of Species (B) Signup and view all the answers

What term describes species that are naturally found only in a particular location?

Endemic (D) Signup and view all the answers

The presence of similar characteristics in two species from different lineages that do not share a recent common ancestor is an example of what evolutionary process?

Convergent evolution (D) Signup and view all the answers

Which of the following is an example of a transitional form in the fossil record?

The Fishapod (Tiktaalik roseae) (A) Signup and view all the answers

Which concept refers to a fundamental similarity between species due to shared ancestry?

Homology (B) Signup and view all the answers

Which group of mammals is not native to Australia?

Placental Mammals (C) Signup and view all the answers

What is the primary role of genetic variation in the process of evolution?

It enables natural selection to increase or decrease the frequency of alleles. (C) Signup and view all the answers

Which of the following best describes the concept of natural selection?

Individuals with traits that make them better suited to the environment are more likely to survive and reproduce. (B) Signup and view all the answers

What is the source of new alleles in a population?

Genetic mutations. (C) Signup and view all the answers

How does artificial selection differ from natural selection?

Artificial selection is driven by humans choosing desirable traits, while natural selection is driven by environmental factors. (C) Signup and view all the answers

What was the direct impact of the 1977 drought on the medium ground finches of Daphne Major?

It resulted in larger average beak sizes in the offspring. (A) Signup and view all the answers

Which of the following is a result of selective breeding programs?

The modification of traits in domesticated species. (C) Signup and view all the answers

The Spirit Bear is an example of a:

Phenotype arising from a recessive mutation. (D) Signup and view all the answers

Which factor is NOT considered a source of genetic variation?

Phenotype selection. (D) Signup and view all the answers

Which of the following BEST describes the theory of uniformitarianism?

The concept that Earth is far older than 6,000 years and has been slowly shaped by geological processes over vast time periods. (B) Signup and view all the answers

What was a key contribution of Thomas Malthus that influenced Darwin's thinking?

The idea that not all individuals in a population survive and reproduce. (A) Signup and view all the answers

What was the primary contribution from Erasmus Darwin to the theory of evolution?

Suggesting life on Earth may have descended from a common ancestor. (D) Signup and view all the answers

What did Darwin observe on the Galapagos Islands that significantly influenced his theory of evolution?

Variations in finch beak shapes which were suited to different diets. (D) Signup and view all the answers

What is the central idea of Darwin's theory of evolution?

Species evolve from pre-existing species through natural selection. (A) Signup and view all the answers

What important idea did Alfred Wallace independently develop at the same time as Darwin?

The theory of evolution by means of natural selection. (D) Signup and view all the answers

Which of these was NOT mentioned in the text as a key influence on Darwin’s thinking?

The study of genetics and DNA. (A) Signup and view all the answers

Which of the following best describes the concept of microevolution?

Changes in a single gene or allele frequencies within a population over time. (A) Signup and view all the answers

According to the information, what are the two interacting factors driving evolution from generation to generation?

Variations in heritable traits and natural selection. (B) Signup and view all the answers

What is the primary distinction between a species and a population?

A species is a group of related organisms with a distinctive form, while a population consists of members of the same species in the same area that can interbreed. (C) Signup and view all the answers

Which of these concepts did Theodosius Dobzhansky emphasize regarding biology?

Evolution is the fundamental framework required to understand biology. (D) Signup and view all the answers

What was the key shift in thinking during the scientific revolution of the 1600s?

Reliance on observation and experimentation to form ideas and hypotheses. (D) Signup and view all the answers

What was John Ray's contribution to the study of the natural world?

Developing an early classification system based on anatomy and physiology, and establishing the modern species concept. (B) Signup and view all the answers

What is the significance of Carl Linnaeus's binomial system of nomenclature?

It provided a two-part naming system for organisms that helped scholars perceive similarities and differences. (C) Signup and view all the answers

What key idea did Jean-Baptiste Lamarck propose regarding the evolution of species?

Species evolve by adapting to their environments, and these adaptations are passed down to offspring. (C) Signup and view all the answers

What is meant by the 'inheritance of acquired characteristics,' as proposed by Lamarck?

Changes in an organism's traits due to environmental factors, which are then inherited by its offspring. (B) Signup and view all the answers

What is the primary distinction between orthologous and paralogous genes?

Orthologs are homologous genes found in different species, while paralogs are homologous genes within a single species. (A) Signup and view all the answers

Which of the following best describes vestigial structures?

Structures that have no current function but resemble those of presumed ancestors. (D) Signup and view all the answers

Which of the following is a feature of molecular homology?

The use of DNA to store genetic infromation and various biochemical pathways found across nearly all species (D) Signup and view all the answers

How does horizontal gene transfer differ from vertical evolution?

Horizontal gene transfer involves the direct incorporation of genetic material from another organism, while vertical evolution is the accumulation of genetic changes in a species. (C) Signup and view all the answers

What is the significance of gene families?

They allow for specialized functions, expression at different times, or in different tissues for homologous genes. (B) Signup and view all the answers

What is the evolutionary significance of anatomical homology observed in vertebrate forelimbs?

Vertebrate forelimbs share a common set of bones that have been modified for different functions in different species, indicating a common ancestral origin. (A) Signup and view all the answers

How do developmental homologies in embryos support the concept of evolution?

They show that species that differ as adults often bear striking similarities during early embryonic development, indicating shared ancestry. (B) Signup and view all the answers

What is the significance of independent accumulation of different random mutations in homologous genes?

It may cause homologous gene sequences to be similar, but not identical, as they evolve. (A) Signup and view all the answers

Study Notes

BIOL 1P92 Course Information

Course name: BIOL 1P92
Course description: Introduction to Biology II
Instructor: Dr. Szuroczki
Co-ordinator: Katie Hunter ([email protected])
Important contact for lab grades: Dr. Martin ([email protected])
Required textbook: Biology 6e W/Connect (2 Years Access) Ed: 6
Textbook authors: Brooker, Widmaier, Graham, Sti
Textbook ISBN: 9781265396138
Publisher: McGraw Hill
Connect platform: Suggested but not required

Course Marking Scheme

Midterm Test: 30% (Week 1-3 content covered by Dr. Szuroczki)
Final Exam: 35%
Laboratory assignments: 35%

Topic Schedule

Chapter 22: Introduction to Evolution
Chapter 23: Population Genetics (Microevolution)
Chapter 26.1-26.2: History of Life on Earth
Chapter 24: Origin of Species (Macroevolution)
Chapter 25.1-25.3: Taxonomy & Phylogenetics
Chapter 27-29: Biodiversity (Bacteria, Archaea, Protists, Fungi) in an Evolutionary Context
Chapter 31: Evolution of Land Plants & Charophycean Algae
Chapter 33: Animal Diversity & Choanoflagellates
Chapter 34,35.1: The Invertebrates & Vertebrates
Chapter 41,47.4: Animal Bodies & Homeostasis
Chapter 42.1-42.4: Neuroscience

Key Concepts

Overview of Evolution
Evidence of Evolutionary Change
The Molecular Processes that Underlie Evolution

Introduction and Definitions

Evolution: Heritable change in one or more characteristics of a population or species from one generation to the next
Microevolution: Viewed on a small scale; changes in a single gene or allele frequencies in a population over time
Macroevolution: Viewed on a larger scale; Formation of new species or groups of related species
Species: Group of related organisms that share a distinctive form
Population: All members of the same species that live in the same area at the same time and have the opportunity to interbreed

Scientists Who Set the Stage

John Ray (mid- to late-1600s): First to carry out a thorough study of the natural world, developed an early classification system.
Carl Linnaeus: Extended John Ray's work to develop the binomial system of nomenclature (Homo sapiens).
Georges Buffon: Suggested life forms change through time.
Jean-Baptiste Lamarck: Hypothesized that species change over many generations by adapting to their environments (Inheritance of acquired characteristics).
Erasmus Darwin: Early advocate of evolutionary change and suggested common ancestry.

Inheritance of Acquired Characteristics (Lamarck)

Organisms change their behavior in response to environmental changes, modifying traits
Modifications are then inherited by offspring
Example: Giraffes stretching their necks to reach higher leaves, leading to longer necks in subsequent generations

Influence from Other Fields of Study

Uniformitarianism: Slow geological processes lead to substantial change, Earth is older than 6,000 years
Catastrophism: Belief that Earth's features are formed by short-lived violent events.
Thomas Malthus: An economist whose essay on population growth (1798) showed that not all members of a population will survive and reproduce.

Charles Darwin

Born in 1809
Played a central role in developing the theory of evolution, suggesting that existing species evolved from pre-existing species.
Key influence: Voyage on HMS Beagle (1831-1836), particularly observations of Galapagos finches.
Theory of Evolution: Descent with modification through variation and natural selection (two interacting factors) - Variation: Traits varying in individuals and are heritable. Genetic basis not known at that time. - Natural selection: Individuals with traits better suited to the environment flourish and reproduce; others less likely
Published On the Origin of Species in 1859
Alfred Wallace: Sent Darwin an unpublished manuscript with similar ideas in 1858

Darwin's Theory of Evolution (in depth)

Variation in traits: Individuals within a population vary in heritable traits
Natural selection: Individuals better suited to the environment are more likely to survive and reproduce, passing traits to the next generation.
Favorable traits increase in the population over time

Source of Genetic Variation

Genetic variation: An important force in evolution because it allows natural selection
Can be caused by mutation (creating new alleles)
Random mating, random fertilization, and recombination during meiosis

Evolutionary adaptation by Natural Selection

Natural selection favors traits that enhance survival and reproduction in a given environment
Example: Galapagos finches - beak size adaptation as a response to seed availability
Example: The evolution of finches adapting to larger seeds in a drought

Examples of Natural Selection

Daphne Major: Medium ground finches; beak depth as a heritable trait was studied over 40 years; severe drought in 1977 resulted in fewer smaller seeds; offspring had larger beak size in 1978.

Selective Breeding

Programs and procedures to modify traits in domesticated species
Artificial selection: Breeders choose the parents with desirable traits
Different from natural selection in the choice of parents

Example: Darwin's Pigeons

Darwin studied rock pigeon varieties in his work "Variation in Animals and Plants under Domestication"
Drawings of variations in pigeons

Example: Wild Mustard

Illustrates how selective breeding can change traits in plants
Wild mustard can be bred into different varieties (e.g., Kohlrabi, Kale, Broccoli, Brussels sprouts, Cabbage, Cauliflower)

Biogeography

Study of the geographic distribution of extinct and living species
Isolated continents and island groups have evolved distinct plant and animal communities
Endemic Species: Naturally found only in a particular location. Ex: Island fox, evolved from mainland fox during ice ages

Example: Australia

First mammals arose before Australia separated
Australia has no native large terrestrial placental mammals but has marsupials.

Convergent Evolution

Species from different lineages evolve similar characteristics because they occupy similar environments.
Analogous structures and convergent traits are not similar due to shared evolutionary history.

Fossil Record

Fossils are compared according to age (oldest to youngest)
Reveals successive evolutionary change
Transitional forms: Fossils providing a link between older and younger fossils/species.

Example: Fish-like Tetrapod (Tiktaalik roseae)

Transitional form between fishes and tetrapods
Characteristics: Broad skull, flexible neck, eyes on top of head, primitive wrist, finger-like bones
Could peek above water and look for prey

Example: Evolution of Whales

Order Cetacea (whales, dolphins, porpoises)
Closest relatives: hippos
Evolved from terrestrial tetrapods over 50 million years to aquatic animals without hind limbs.

Homology

Fundamental similarity due to descent from a common ancestor
Anatomical homology: Modern vertebrates have a similar set of bones in their forelimbs despite their different functions
Developmental homology: Species that differ as adults often bear striking similarities during early embryonic development (e.g., gill ridges, bony tails). Examples of species from different lineages that share common development-related homologous structures: Lizard, Tortoise, Pig, Human
Molecular homology: Similarities at the molecular level (e.g., DNA sequences, biochemical pathways) indicate that living species evolved from a common ancestor
Homologous Genes:* Two or more genes derived from the same ancestral gene. In different species, they are called orthologs. Two sequences may be similar, but not identical, due to independent accumulation of different random mutations.
Gene Families:* Two or more homologous genes in a single species; called paralogs. These are generated by gene duplication events within a genome of a single organism. An example is the globin family (myoglobin, cytoglobin, different forms of hemoglobin).

Horizontal Gene Transfer

Organisms incorporate genetic material from other organisms without being offspring from those organisms
Widespread among bacteria

Evolution at the Genome Level

Evolutionary changes at the genome level involves changes in chromosome structure and number because these changes can influence the ability of two organisms to breed with another. This can also be an important factor in establishing new species.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your understanding of key concepts covered in the first three weeks of Biology 101. The quiz includes questions about evolution, the fossil record, and species characteristics. Perfect for students looking to reinforce their knowledge of the history of life on Earth.