Write each slide title on the left side of the paper Notes HW Write each slide title on the left side of the paper Summarize provided information on the right side of the paper If there are slides with Objectives or “this lecture will help you understand” you do NOT need to write these. Define any words or answer any questions or fill in the blanks when something appears in red. Sometimes it is a question linked to a website you should view Sometimes there are comments written in purple. You do not need to write these. They are just my personal commentary  Be prepared to answer questions at the end.

This lecture will help you understand: Natural selection How evolution influences biodiversity Reasons for species extinction Ecological organization Population characteristics Population ecology Conserving biodiversity

Central Case Study: Saving Hawaii’s Native Forest Birds Evolution in the Hawaiian Islands has generated hundreds of species, many unique to the islands The island chain was once home to 140 species of native birds In recent times, half of the native bird species have gone extinct Introduced species (like pigs, cattle, rats, and cats) destroyed habitat and killed eggs and young Avian malaria killed native birds at lower elevations

Evolution: The Source of Earth’s Biodiversity Species? They can breed with one another and produce fertile offspring Population? Evolution? Biological evolution? What happens with genetic change?

Evolution: The Source of Earth’s Biodiversity Genetic changes happens (randomly or systematically?) But may be directed by natural selection Natural selection? What happens to the genetic makeup of future populations?

Natural selection shapes organisms and diversity In 1858, both Darwin and Wallace proposed natural selection as the mechanism of evolution What are the three premises of natural selection? Organisms with better adapted traits will produce more offspring

Natural selection shapes organisms and diversity Adaptation? Adaptive trait (adaptation)? Mutations? Non-lethal mutations provide the genetic variation on which natural selection acts Sexual reproduction also leads to variation What is directional selection?

Selective pressures from the environment influence adaptation __________ species in different environments experience different pressures and evolve different traits Convergent evolution?

Evidence of natural selection is all around us It is evident in every adaptation of every organism Artificial selection? What are two examples that we use artificial selection?

Evolution generates biodiversity Biological diversity (biodiversity)? How many species have scientists identified so far? Estimates of the total number of species that exist range from ___ million to ___million

Speciation produces new types of organisms What is Speciation? Allopatric speciation? The_________mode of speciation Populations can be separated by glaciers, rivers, mountains Each population gets its own set of ____________ _______________can speed the process

We can infer the history of life’s diversification by comparing organisms How did the major groups of organisms come to be? What are phylogenetic trees? What can scientists trace one these trees are constructed? Can traits evolve more than once?

We can infer the history of life’s diversification by comparing organisms Knowing how organisms are related to one another helps scientists___________and_________them Categories reflect evolutionary relationships Scientists use____________and_____________characteristics to organize Each species gets a_____________Latinized scientific name

The fossil record teaches us about life’s long history These records help to reveal the history of life on earth.

Speciation and extinction together determine Earth’s biodiversity Species last 1–10 million years Extinction has historically been a natural occurrence The loss of a species is _____________ How do we calculate the number of species in existence?

Speciation and extinction together determine Earth’s biodiversity Human activity profoundly affects rates of extinction How does biodiversity loss affect humans directly?

Some species are especially vulnerable to extinction Endemic species? Very susceptible to extinction Usually have ________populations ________species are often endemic and thus at risk

Earth has seen several episodes of mass extinctions A constant, slow rate of extinction that occurs as a part of evolution is known as__________________ Mass extinction events? Occurred five times in Earth’s history __________of all species go extinct at one time

The sixth mass extinction is upon us Humans are causing the sixth mass extinction event Resource depletion, population growth, development Destruction of natural habitats Hunting and harvesting of species Introduction of non-native species Today’s extinction rate is____________times higher than the background rate and rising

We study ecology at several levels Levels of Ecological Organization Biosphere? Community? Ecosystem?

We study ecology at several levels Population ecology? Community ecology? Ecosystem ecology? Nutrient and energy flows

Each organism has habitat needs Does the habitat include abiotic and biotic factors? Habitat use? Results in (random or non-random) patterns of use Habitat selection? What can potentially cause conflict with habitat selection?

Each organism has habitat needs Habitats vary with the body size and needs of species A soil mite vs. an elephant Species have different habitat needs at different times Migratory birds use different habitats during migration, summer, and winter Species use different criteria to select habitat Soil, topography, vegetation, other species Water temperature, salinity, prey Species survival depends on having suitable habitat

Niche and specialization are key concepts in ecology Use of resources What are some functional roles in a community?

Niche and specialization are key concepts in ecology Specialists? Are vulnerable when conditions change or remain constant? Generalists? Use a wide array of habitats and resources Can live in the same or different places?

Population Ecology Population? What is the difference between an isolated and continuous population?

Populations show characteristics that help predict their dynamics Population size? Populations generally grow when resources are (more or less) and when there is (a lot or few) predators Population size will (rise or decline) in response to loss of resources, other species, disasters

Population density Population density? Give the advantages and disadvantages of a high density population. Give the advantages and disadvantages of a low density population.

Population distribution Population distribution (dispersion)? Haphazardly located individuals, with no pattern is_____________ Individuals are evenly spaced is ________________ Territoriality, competition Organisms found close to other members of population is ________________________

Sex ratio and age structure In monogamous species, a_____sex ratio maximizes population growth Age distribution (structure)? Age structure diagrams (pyramids) show the age structure of populations In species that continue growing as they age, older individuals reproduce more Give an example of a species that reproduce more as they age.

Birth and death rates Survivorship curves? Type I: higher death rate at older ages Larger animals (humans) Type II: same death rate at all ages Medium-sized animals (birds) Type III: higher death rate at young ages Small animals, plants

Populations may grow, shrink, or remain stable What is the difference between natality and mortality? Immigration? Emigration? What are some ways the individuals are added to a population? What are some ways that individuals are removed from the population? How do we find the crude birth (death) rates?

Populations may grow, shrink, or remain stable Natural rate of population increase = (Crude birth rate) − (crude death rate) Population change due to internal factors Population growth rate = (Crude birth rate + immigration rate) − (Crude death rate + emigration rate) Net changes in a population’s size/1000/year Growth rate as a percent = Population growth rate × 100% Populations of different sizes can be compared

Unregulated populations increase by exponential growth What is the curve shape of exponential growth? Exponential growth cannot be sustained indefinitely Where does exponential growth occur?

Limiting factors restrain population growth Physical, chemical, and biological attributes of the environment that restrain population growth are_________________ Give some examples of limiting factors. Carrying capacity? Limiting factors slow and stop exponential growth An__________logistic growth curve

The influence of some factors depends on population density What are Density-dependent factors? Increased density increases? Results in the__________________curve _______________populations have weaker or stronger effects of limiting factors Density-independent factors = limiting factors whose influence is not affected by population density What events are considered d.i.f.?

The logistic growth curve is a simplified model Few populations in nature match the curve exactly

Carrying capacities can change Environments are complex and always changing. Limiting factors change and alter the carrying capacity Humans lower environmental resistance for themselves Increases or decreases our carrying capacity? Technologies overcome limiting factors In increasing carrying capacity for humans, we now use immense portions of the planet’s resources We have reduced the carrying capacity for countless other organisms

Reproductive strategies vary among species Biotic potential = an organism’s capacity to produce offspring K-selected species? Have a low or high biotic potential Stabilize at or near carrying capacity; good competitors r-selected species? Have a high or low biotic potential Populations fluctuate greatly These are the two extremes—most species fall somewhere in between

Innovative solutions are working Scientists, land managers, and private citizens are protecting the native species and habitats of Hawaii Invasive species are being added or removed? Native species (like the nēnē) are being protected, and new populations are being started Ranch land is being restored to forest Coral reef communities are part of the largest federally protected marine reserve in the world This restored and protected land has resulted in ecotourism. What is ecotourism?

Climate change now poses an extra challenge Climate change is altering how we protect species and habitats Land is typically protected to conserve the species that live there As the climate changes, the protected land may no longer support the same species

Conclusion The fundamentals of evolution and population ecology are integral to environmental science Natural selection, speciation, and extinction help determine Earth’s biodiversity Understanding how ecological processes function at the population level is crucial to protecting biodiversity

QUESTION: Review Which of the following is NOT a part of the process of natural selection? Once grown, organisms generally do not have to struggle to survive. Organisms produce more young than can survive. Individuals vary in their genetic characteristics. Some individuals are better suited to their environment than others. Answer: a 54

QUESTION: Review What happens as a result of adaptation? Species have lower reproductive success and lower survival. Species have higher reproductive success and higher survival. Species have higher reproductive success and lower survival. Species have lower reproductive success and higher survival. Answer: b 55

QUESTION: Review Directional selection would result in which of the following? Dogs with black coats evolving whiter coats in colder areas Red and white flowers interbreeding, producing pink flowers Fish evolving bigger eyes as the water gets muddier A population of birds, some with thicker beaks that eat seeds and others with thinner beaks that eat insects Answer: c 56

QUESTION: Review Allopatric speciation would occur in one population that mates in May and another that mates in June. two populations separated by the Mississippi River. one population that feeds in tree branches and another that feeds on tree trunks. a population with a mutation that turns fur a different color than usual. Answer: b 57

QUESTION: Review Which of the following statements about extinction is true? Extinctions have only started now that humans are changing the planet. Extinction of one species never benefits any other organisms in a community. The vast majority of species that have ever existed are now extinct. Extinction rates stay at a constant background rate and never change. Answer: c 58

QUESTION: Review Which of these species is MOST vulnerable to extinction? A species whose crude death rate is lower than its crude birth rate A species distributed in one county of the United States A species that eats many different plant species A species that has hundreds of offspring Answer: b 59

QUESTION: Review A community is defined as the total of living things on Earth. members of the same population that can interbreed. interacting species in an area. species and the nonliving material they interact with. Answer: c 60

QUESTION: Viewpoints Should we care whether a species goes extinct? Yes, because all life is important and valuable. Yes, because we are causing this wave of extinction, so we should fix it. We should not, because it’s natural. I don’t care; it really does not affect me. Answer: any 61

QUESTION: Viewpoints Do you think humans are subject to limiting factors and, ultimately, a fixed carrying capacity? Yes. Although we have raised the carrying capacity, there are limits to the number of humans Earth can support. Yes, but technology will keep raising the carrying capacity, so it’s not much of a problem. No. Humans are no longer constrained by environmental limits, due to our technology and ability to manipulate the environment. I don’t care; it really does not affect me. Answer: any 62

QUESTION: Interpreting Graphs and Data Which type of distribution is a result of competition between individuals? Random Uniform Clumped None of these Answer: b 63

QUESTION: Interpreting Graphs and Data What does this graph show? The effects of carrying capacity on population growth A population that keeps growing The effects of exponential growth The effects of increasing carrying capacity Answer: a 64