Lecture 1: Intro to Ecology PDF

Preview

Summary

Lecture 1: Introduction to Ecology
Intro to BIOL2101 course by Mennill...

Description

LECTURE 1: INTRODUCTION TO ECOLOGY Rufous-and-white Wren - Thryophilus rufalbus - Main organism Den Mennill studies - Uses a mark and recapture method to study this organism - Nest is a large woven structure, tunnel shaped with a roof on top - Always builds their nests in bullhorn acacia trees (Vachellia collinsii) Bullhorn Acacia - Stems and branches are studded with thorns to prevent it from being eaten - Grows in an area with no other vegetation - Dan was bitten by an ant while climbing an acacia tree Acacia ant - Pseudomyrmex ferruginea - Makes its home in the bullhorns as they are growing, nests its eggs in the bullhorns - Ant has an advantage; has access to all food and water it needs - Bullhorn emits sap from nectary, key source of glucose - Beltian body on the tree is a packet of fat and protein for the ant Mutualistic relationship - mutualism - The ants defend the tree by attacking herbivores - The tree provides nutrients and a home to the ants - Ants wander around the tree and clear out any vegetation during growing season - Provides an advantage to the tree Wasps - Try to exploit the ant & tree mutualistic relationship - Wasps are protected by the ants because the ants protect the tree - Parasitic relationship? Wren - Wren is provided defence by the ants - The ants give up defending once the nest is built by the wren - Vine snakes are a prime predator to vine snakes, but the acacia ant’s venom is toxic to them Relationships - Wrens and wasps → parasitic relationship with three ants/tree

-

Acacia and and acacia tree → mutualism relationship Plants, monkeys, deer, snakes all defended against

What is Ecology? - The study of relationships between organisms and their environment - The word ecology was coined in 1869; Oikos meaning home and Logos meaning Study of - Ecology is separate from natural history - The descriptive study of organisms in their natural habitats → Darwin (ecology asks why is the animal in this habitat?) - Systematic and quantitative enterprise Abiotic Environmental Factors - Non-living environmental factors that influence organisms in an environment - Temperature, moisture, nutrients, fire, or toxins Biotic environmental factors - Living environmental factors that influence an organisms environment - Competition, herbivory, predation, parasitism, disease, mutualism Ecosystems - Fundamental unit in ecology - Include abiotic and biotic components - Can be large (biosphere) or small (pitcher of a pitcher plant) Ecosystems - The function of an ecosystem is described by productivity (rate in increase of biomass), changes in nutrients (eg. nitrogen fixation), the flow of energy, and flow of water Ecology is a science - Common features of ecological studies: - Field based research - Sophisticated tools (noise, camera, etc) - Hypothesis testing (“we think traffic noise affects birds..”) - Statistical analysis - Ecologists will propose a testable hypothesis that is related to the organization and function of the natural world Ecology is applicable - Ecology can be applied to management of different resources

Different types of ecology - Conservation ecology: application of ecology to biodiversity issues - Systems ecology: holistic studies of ecosystems - Paleoecology: prehistoric ecosystems and their components - Evolutionary ecology: evolutionary aspects of adaptive changes - Statistical and mathematical ecology: numerical methodologies - Theoretical ecology: theories of structural and functional aspects of ecosystems - Landscape ecology: examination of ecosystem structure and function at large spatial scales - Environmental ecology: environmental and sustainability issues - Applied ecology: use of ecological knowledge to deal with economic problems - Population ecology: dynamics of species, including biological and environmental influences - Restoration ecology: repair of ecological damage - Community ecology: interactions among species within communities - Behavioural ecology: behavioural responses to environmental conditions - Functional ecology: energy and nutrient flows between ecosystems and abiotic environment...