Species, Populations, and Communities
This segment of the environmental science course focuses on the biotic, or living parts of the environment. Students will learn about the importance of biodiversity, the interconnectedness of life, and the different types of relationships all living things share with each other. This unit also includes a brief introduction to natural selection and its relationship to the diversity of forms seen throughout the biosphere.
Species, Populations, and Communities Lecture Powerpoint
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Purpose: This lecture introduces students to the first three levels of ecological organization: species, populations, and communities. After a brief overview of evolution and natural selection, students will be shown each of the different types of symbiotic, competition, and predator-prey relationships. Different types of niches will also be explored as students learn the role of individual species within a community.
Essential Concepts: Ecological organization, populations, communities, niche, species interactions, symbiosis, mutualism, commensalism, parasitism, intraspecific competition, interspecific competition, predator, prey, food web, evolution, natural selection, artificial selection, K-strategists, r-strategists.
Species, Populations, and Communities Lecture Notes Outline
Purpose: Taking efficient notes can be a big challenge for many students, especially when working from a Powerpoint lecture. This outline gives students a means to take notes that guides them toward important concepts and avoids the pitfalls of writing word-for-word or simply not taking notes at all. The outline is written as a series of questions, fill-in-the-blanks, or diagrams.
Essential Concepts: Ecological organization, populations, communities, niche, species interactions, symbiosis, mutualism, commensalism, parasitism, intraspecific competition, interspecific competition, predator, prey, food web, evolution, natural selection, artificial selection, K-strategists, r-strategists.
PBS Evolution Series "Why Sex?" Video Worksheet
Purpose: Evolution is a six-part documentary created by NOVA in 2001. Each episode covers a different aspect of evolution. While each episode is exceptionally well-done, the "Why Sex?" episode is particularly relevant to this chapter. This documentary explores the evolutionary advantage sexual reproduction has over asexual reproduction. Multiple examples throughout both the human world and the animal world are analyzed.
Essential Concepts: Evolution, natural selection, sexual selection, sexual reproduction, asexual reproduction, adaptations.
Journal Writing Assignment: Evolution and Human Behavior
Purpose: This writing prompt is intended as a follow-up assignment to a viewing of the PBS Evolution episode entitled "Why Sex?". The documentary proposes several intriguing hypotheses relating human behavior to natural selection. Students will examine some basic human behaviors and discuss whether they are rooted in evolution or in our environment and upbringing.
Essential Concepts: Evolution, natural selection, sexual selection, human behavior, adaptations.
Journal Writing Assignment: Adaptations
Purpose: Students with a firm grasp of the theory of natural selection should begin to observe it in the world around them. The biological design of every organism has a purpose. One of the best places to start is with the extraordinary diversity of multicellular life found all over the Earth. This assignment requires students to choose a multicellular organism, identify each of its adaptations, and relate these adaptations to the organism's habitat and niche.
Essential Concepts: Evolution, natural selection, adaptations, habitat, niche, biodiversity.
Construct a Phylogenetic Tree Activity
Purpose: One of the best ways to visualize evolutionary relationships is by drawing a phylogenetic tree, also known as a "tree of life". This activity has students construct their own tree from a set of animals provided, using only specific, observable physical differences. This activity gives students an opportunity to classify organisms on their own, and begin to visualize the types of evidence used to show their evolutionary relationships.
Essential Concepts: Evolution, natural selection, adaptations, habitat, niche, biodiversity, classification, phylogenetic tree.
BBC Blue Planet "Coral Seas" Video Worksheet
Purpose: The seas surrounding coral reefs have the most diversity of any of the aquatic ecosystems. With such a wide abundance of life, a wide variety of complex relationships can be seen between the different animals and plants within the ecosystem. This episode of the BBC Blue Planet series illustrates wonderful examples of parasitism, mutualism, commensalism, competition, and predation.
Essential Concepts: Coral reefs, symbiosis, competition, predation, parasitism, commensalism, mutualism, coral reef, adaptations, aquatic ecosystems.
Species, Populations, and Communities Study Guide
Purpose: Once the instruction for the unit is completed, students can complete this study guide to aid in their preparation for a written test. The study guide is divided into two sections: vocabulary and short answer questions. The vocabulary is taken directly form the lecture, sequentially. The short answer questions are meant to model the type they may see on the exam.
Essential Concepts: Ecological organization, populations, communities, niche, species interactions, symbiosis, mutualism, commensalism, parasitism, intraspecific competition, interspecific competition, predator, prey, food web, evolution, natural selection, artificial selection, K-strategists, r-strategists.
