The theme of this guide is the protection and maintenance of diverse shark populations by understanding the effect that overfishing has on ocean ecosystem food webs
Studying life on the seafloor beneath Antarctica's thick ice is a major challenge for ecologists. Learn about a new device that can reach those icy depths in this video segment adapted from WomenInAntarctica.com.
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:
"Roundup is the most widely used non-selective herbicide, but it’s also one of the most controversial on the market. Much evidence about Roundup's safety is based on toxicity tests that, despite being outdated, are routinely used by regulators and say little about the long-term, sublethal effects of Roundup or its active ingredient glyphosate. Now, a new study has taken a systems biology approach to examine the effects of Roundup on organisms at at the genomic and fitness level. Daphnia are not a Roundup target but are exposed to the herbicide through run-off from farmlands and they are central to aquatic food webs. In the lab, Daphnia were exposed to the regulatory threshold concentration of glyphosate and Roundup. Researchers found that chronic exposure to either chemical had highly detrimental effects including embryonic developmental failure, DNA damage, and signaling interference. Daphnia also showed changes in their microbiome and disruptions in metabolism..."
The rest of the transcript, along with a link to the research itself, is available on the resource itself.
Student teams investigate the migration of small-particle plastic pollution by exposing invertebrates found in water samples from a local lake or river to fluorescent bead fragments in a controlled environment of their own designs. Students begin by reviewing the composition of food webs and considering the ethics of studies on live organisms. In their model microcosms, they set up a food web so as to trace the microbead migration from one invertebrate species to another. Students use blacklights and microscopes to observe and quantify their experimental results. They develop diagrams that explain their investigations—modeling the ecological impacts of microplastics.
This nonfiction article, written for students in grades 4-5, explores the relationships between various tundra species: marsh marigolds, bot flies, and caribou. Modified versions are available for students in younger grades.
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:
"Across all three domains of life, organisms have adapted to earth’s natural light-dark cycle, setting their genetic, metabolic, and behavioral clocks to it. That includes the single-celled cyanobacterium Prochlorococcus, one of the most dominant phytoplankton in the oceans. Recent lab experiments revealed that cyanophages, viruses that infect Prochlorococcus, also show light-dark rhythms and express different genes according to their stage of infection: early, middle, or late. But whether that phenomenon occurs in the open ocean remained unclear. To find out, researchers analyzed genetic material from the North Pacific Subtropical Gyre. They set out to test whether cyanophages express infection genes in unsynchronized or synchronized patterns. In unsynchronized expression, early, middle, and late infection genes are transcribed at any time. While in synchronized expression, gene transcription evolves with the time of day. Early genes, for example, are expressed at sunrise and late genes close to sunset..."
The rest of the transcript, along with a link to the research itself, is available on the resource itself.
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