Organisms: Introduction

Digest

Approach

• Constructive approach: Building up from organisms to populations to communities.
• Analytically approach: Deconstructing from communities into populations and furthermore into organisms.
• This book follows a constrictive rather than analytically approach in this regard.

Constructive approach

Chatpers

1. Chapter 1: Constraints of evolutionary history of organisms
2. Chapter 2: Variation of environmental conditions with respect to place and time and their effect (limit) on the distribution of particular species.
3. Chapter 3: Resources consumed by different types of organisms.
4. Chapter 4: Variety in the schedules of birth and death (life histories)
5. Chapter 5: Intraspecific competition for shared resources in short supply (interaction within single species populations)
6. Chapter 6: Immigration and emigration
7. Chapter 7: Applications: restoration, biosecurity, species conservation

Questions

1. What role does the abundance of a specific species play in shaping a community?
2. What will the chapters in Part I (Organisms) be covering?

Introduction: Definition and Scope of Ecology

Answers

1. Ecology is the scientific study of the distribution and abundance of organisms and the interactions that determine distribution and abundance.
2. This section does not cover the uses of ecology. Ecology covers organisms, populations, communities and ecosystems.

Digest

• definition of ecology
• history of how ecology was defined:
• 1869 by Ernest Haeckel: Ecology is the scientific study of interactions between organisms and their environment. Haeckel is the one who coined the term ecology.
• 1972 by Krebs: "Ecology is the scientific study of the interactions that determine the distribution and abundance of organisms."
• Preferred definition: "Ecology is the scientific study of the distribution and abundance of organisms and the interactions that determine distribution and abundance."
• 1992 by Likens: "Ecology is the scientific study of the distribution and abundance of organisms and the interactions between organisms and the transformation and flux of energy and matter."
• Two approaches to taken by ecologists at each level of ecological organisation:
• Building from properties at the level below: ex: physiology when studying organismal ecology
• Directly with properties of the level of interest: ex: rate of biomass production at the ecosystem level
• Biological hierarchy
• subcellular particle
• cell
• tissue
• organ
• Ecological organization:
• organism
• population (individuals of the same species)
• community (a number of species populations)
• ecosystem (community plus physical environment)
• biotic vs. abiotic

Ecological Organization

Questions

1. What is the definition of ecology?
2. What are the uses of ecology and what does it cover?