CHAPTER 50 – AN INTRODUCTION TO ECOLOGY AND THE BIOSPHERE

1. CHAPTER 50 – AN INTRODUCTION TOECOLOGY AND THE BIOSPHERE Objectives of Learning: Interactions between organisms and their environments determine the abundance and distribution of organisms Ecology and Evolutionary Biology are closely related Species dispersal, behavior, habitat, abiotic and biotic factors contribute to the distribution of organisms Temperature and water are major climatic factors that determine distribution of organisms Biomes are determined by yearly temperature, rainfall, and geography Themes: Interaction with the environment, Unity and Diversity, Evolution

2. Root Words • Oligo- • Meso- • Micro- • Pelag- • Perman- • -photo • Profund- • -clin • A- • Bio- • Abyss- • Bentho- • Estuar- • Eu- • Troph- • Geo- • Hydro- • Therm- • Inter - • Limn- • Littor-

3. IMPORTANT IDEAS: A. Ecology – study of the interaction of organisms & their environment. Organism Organism Environment 1. Abiotic Factors – nonliving factors (Temp. pH, rainfall etc.) 2. Biotic Factors – living factors. B. Levels of Organization in Ecology – (in order of least to most inclusive) Individual Population Community Ecosystem Biomes Biosphere

4. Population – Group of the SAME species (Given area/given time). Community – Group of different populations. Ecosystem – All organisms in an area as well as the ABIOTIC factors. Biome – World’s major communities. Key Factors – climate, topography which determines predominant vegetation, which in turn determines type of organisms and their adaptations to their environment. Climate – average daily weather conditions in an area. ( Controlled by: Temp, precipitation, winds, and light.) Microclimate – climate within climates. Topography – Physical features of the land. (Mountains, plains, valleys etc.) Biosphere – entire portion of the earth inhabited by life.

5. Other Terms: 1. Acclimation – physiological adjustment to a change in an environmental factor. 2. Morphology – Study of anatomical features. 3. Phytoplankton – Plankton (microscopic) that are plants. 4. Temperature – has the most influence on the metabolic rates of plants and animals 5. Convergent Evolution – species from different evolutionary branches may come to resemble each other if they live in similar roles in the environment. Example – wings of birds and insects. (these are called analogous structures – have similar function, but not necessarily the same shape)

6. Ecotone – an area where different terrestrial biomes grade into each other. Fires – Many plants and animal communities adapt to these. Fires also can change species composition within biological communities. Principle of Allocation – Organisms have limited amounts of energy, so they must allocate their energy for such things as: Getting nutrients; escaping predators; hunting; growth; reproduction etc. Evolutionary Adaptation – is the slowest of all ways organisms respond to environmental changes. (migration is the fastest).

7. Fig. 50.11 pg. 1101 Solar Radiation and Latitude

8. Fig. 50.12 pg. 1102 The Cause of the Season

9. Fig. 50.13 (A) Air Circulation and Precipitation near the Equator Question: If the earth was knocked off its axis and became perpendicular, what is the most obvious effect this would be have? Elimination of seasonal variation.

10. Zonation in a Lake Fig. 50.18 pg. 1107 NOTE: Nutrient-rich runoff into freshwater ecosystems can result in “eutrophication” (nutrient enrichment of a body of water which leads to excessive growth in algae, then depletion of dissolved oxygen as dead algae is consumed by decomposition). Most phytoplankton Bottom dwelling area – the organisms here eat detritus (dead organic material).

11. 50.22 Zonation in Marine Environment Phytoplankton mostly found. Lowest level where photosynthesis occurs

12. Species – most have small ranges in which they live. Introduced species – often fail to colonize the new area; may become common pests; can disrupt the balance of native species Land Biomes As you travel toward the poles Temperature becomes the major factor in determining biomes. Near the equator, precipitation is the major factor. Deserts – are located in places where air masses are usually falling.

13. Aquatic Biomes • Hydrophytes – plants that like to live in very moist soils (grow best in bogs and swamps) • Lake Turnover – in temperate lakes, surface water is replenished with nutrients during turnovers in the spring and fall.

14. Practice Questions: 1. Biome that would support large animals with moderate rainfall? SAVANNA 2. Phytoplankton is found in which zone? PHOTIC (marine). 3. What terrestrial biomes are best adapted to frequent fires? Temperate grasslands, savanna, & chaparral. 4. Different Photoperiods which biome (community) is best adapted? Temperate forest (deciduous) 5. Biome most likely to have a mild climate, rainy winters and hot dry summers? Chaparral