Making direct connections between humanity and the environment is of ever-increasing importance in the context of today's environmental crisis. We used qualitative content analysis of precollege- and college-level introductory environmental science textbook case studies to study how they portray humanity's link to the environment. We assessed case…

This laboratory exercise investigates the influence of population density on offspring number and size in burying beetles. Students test the theoretical predictions that brood size declines and offspring size increases when competition over resources becomes stronger with increasing population density. Students design the experiment, collect and…

A laboratory-based exercise that demonstrates mechanisms underlying leaf degradation in streams. Students examine the effects of "leaf conditioning" on the feeding behavior of invertebrate shredders. The exercise is completed in two sessions and can be adapted to both high school and college levels.

Alkaloids are part of the chemical arsenal designed to protect plants against an adverse environment. Therefore, their synthesis and accumulation are frequently induced in response to certain environmental conditions and are mediated by chemical signals, which are formed as the first responses to the external stimulus. A set of experiments using…

Discusses environmental and biological aspects of arctic and alpine vegetations in the New World between the equator and the Arctic Ocean, considering their similarities, differences, and susceptibility to disturbance by man. (JR)

Presents mathematical models appropriate to describing and analyzing competitive interactions in an ecological system. (MA)

Describes a systems approach from an ecological perspective for teaching the idea of a species and the notion that being a successful species involves being able to overcome certain general problems that must be solved by all species. (PR)

Examines aspects of competitive exclusion, which develops when two species jointly utilize a vital resource that is in short supply. When this occurs, one of the species will eventually eliminate the other from the habitat where their distributions overlap, unless one or both species evolve differences that reduce competition. (JR)

Describes two working models of moths that can be used to test the eyespot function as an aversive property. Uses simple mechanical and electrical models as the "moths" and wild birds as the predators. Includes diagrams, methods, models, validation statements, and a discussion. (RT)

Describes a project designed to increase enthusiasm among college human-ecology students for studying environmental problems. Small groups of students were asked to investigate local pollution problems by first discovering them and then filming them with a mobile videotape unit. (JR)

Discusses some parallels that seem to exist between mass extinction recognizable in the geologic record and the impending extinction of a significant proportion of the earth's species due largely to tropical deforestation. Describes some recent theories of causal factors and periodicities in mass extinction. (Author/TW)

Describes a simplified model for summarizing ecological relationships. The components of the ecological triangle are biotic, abiotic materials, and abiotic conditions. Discusses three-way component interactions, population studies, limiting factors of pollution on humans, and difficulties in establishing casual relationships in field research. (CS)

Suggests that invasion biology can supply subject matter for teaching evolution, genetics, ecological relationships, and conservation. Describes flowering and non-flowering plant invaders, vertebrates and invertebrates, and two ecological invasions on the southern coast of England. (JN)

Discusses how the nature of the rock and, particularly, its fossils can be used in ecology courses for schools and colleges to help students to deduce the nature of the environment at the time the rock was deposited. A checklist and ways of identifying geological sites and fossils are included. (HM)