Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

By the end of this section, you will be able to:Describe the basic types of ecosystems on EarthExplain the methods that ecologists use to study ecosystem structure and dynamicsIdentify the different methods of ecosystem modelingDifferentiate between food chains and food webs and recognize the importance of each

By the end of this section, you will be able to:Describe how organisms acquire energy in a food web and in associated food chainsExplain how the efficiency of energy transfers between trophic levels affects ecosystem structure and dynamicsDiscuss trophic levels and how ecological pyramids are used to model them

By the end of this section, you will be able to:Describe the basic types of ecosystems on EarthDifferentiate between food chains and food webs and recognize the importance of each

By the end of this section, you will be able to:Describe how organisms acquire energy in a food web and in associated food chainsExplain how the efficiency of energy transfers between trophic levels affects ecosystem structure and dynamicsDiscuss trophic levels and how ecological pyramids are used to model them

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Most current knowledge about gut microbiomes has been obtained from studies on mammals, while the microbiomes of fish, the most diverse group of vertebrates (~33,000 species), are less well understood. Specifically, the major influencing factors and unique features of fish gut microbiomes remain unclear. To bridge this knowledge gap, a recent study analyzed the gut contents of 227 fish representing 85 different freshwater fish (FWF) and saltwater fish (SWF) species. rRNA sequencing revealed that Proteobacteria and Firmicutes were the two most abundant phyla, indicating a different composition from the typical vertebrate microbiome, which is composed mainly of Firmicutes and Bacteroidetes. Habitat (freshwater versus saltwater) more strongly influenced the host microbiome than host taxonomy or trophic level and the microbiome taxonomic and functional profiles were better indicators of a fish’s habitat than of its taxonomy..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This activity mimics the ecological energy pyramid using money to represent energy moving between the various trophic levels.

By the end of this section, you will be able to:Describe the basic types of ecosystems on EarthExplain the methods that ecologists use to study ecosystem structure and dynamicsIdentify the different methods of ecosystem modelingDifferentiate between food chains and food webs and recognize the importance of each