Population Ecology

Population Density is the number of organisms per unit of area

Things that affect a Population’s Size (LIMITING FACTORS) Density-Dependent Limiting Factors Competition Predation Parasitism Crowding/Stress   BIOTIC (living) Density-Independent Factors Weather Fires Droughts/ Floods Human Activities   ABIOTIC (non-living)

Predation – what happened to the moose population as the wolf population increased?

Population Growth Rate Growth Rate, Emigration, Immigration, Exponential Growth, Logistic Growth, Carrying Capacity

Population Growth Rate Definition – explains how a population grows Formula to calculate growth rate Births – Deaths = Growth Rate Time

Factors Effecting Growth Rate of a Population Natality – number of births Mortality – number of deaths Emigration – leaving or exiting a population Immigration – moving into a population

Types of Growth in a Population Logistic – population level balances out Births = deaths and/ or… Emigration = immigration

Types of Growth in a Population Exponential Births > Deaths and/ or… Emigration < Immigration

Carrying Capacity Definition – Maximum number of individuals in a species that an environment can support for the long term.

Carrying Capacity

What type of growth is this?

Human Population Growth Rate

Animal Adaptations Behavior Defense Inherited Learned Mechanical Instincts/ Reflexes Territorial Migration Learned Habituation Imprinting Defense Mechanical Chemical

Instinctive Behavior

Territorial Behavior

Migration

Hibernation and Estivation

Cryptic Coloration

Disruptive Color-shading

Counter-shading

Chemical Defenses

Plants adapt to their environment Thorns To stop animals from eating them Thick stems and leaves To hold water Shape Hold water, attract insects Smell Attract and Deter Bright Colors Creative Seeds To be carried by animals, water or wind

Sweet Gum Tree – Seed Pods

Maple Trees – helicopter seeds

Dandelions

Piture Plant

Bromelliad

Cactus

Succulent

Fragrant Flowers

Fragrant Flowers

Brightly-colored Flowers

Brightly-colored Flowers

Geotropism - helps the roots grow down and the stems to grow up

Phototropism Growth of a plant towards sunlight

Thigmotropism – plant’s response to touch – could be due to GROWTH, SEED DISPERSAL, FOOD, PROTECTION

Impatiens capensis https://www.youtube.com/watch?v=wO8-elYLjd4

Plant Hormones Hormone (chemical messenger that plants use to control growth in response to their environment) Auxin – regulates phototropism by stimulating the elongation of cells; keeps fruit from dropping Giberellin – growth hormone that causes a plant to grow taller and increases the rate of seed germination and budding Ethelyene - causes fruit to ripen