Of all the animals in the oceans, the hammerhead shark may be one of the strangest looking. The exact purpose of the wide, flat head is a mystery, but several theories abound. In this video, we travel to the shark-infested waters of the Galapagos in Ecuador and to a research station in Hawaii to learn about the unusual habits of these sinister-looking sharks. Jonathan swims in schools of hundreds of hammerheads, and yet the sharks ignore him. What are the sharks up to? Please see the accompanying study guide for educational objectives and discussion points.

Nassella seeds germinated in water to observe germination process. Photo credit: Fernando Agudelo-Silva

Le site constitue un outil dynamique de détermination des végétaux en ligne, basé sur la manipulation de photos, schémas, glossaire interactif et clés dichotomiques. Le site est accessible à l’adresse: www.biologievegetale.be.
La plate-forme, initialement conçue pour faciliter l’apprentissage des étudiants, constitue également un outil pour le gestionnaire de sites ou le naturaliste. Elle permet d’identifier une espèce végétale à l’aide de clés dichotomiques interactives. Connaître les espèces rencontrées s’avère être la base indispensable pour toute tâche d’évaluation de la structure ou de la qualité d’une végétation. La plate-forme comporte (i) des exercices permettant de s’exercer à la détermination des végétaux. Des liens hypertextes expliquent et illustrent les termes de vocabulaire particuliers. (ii) Une flore en ligne comprenant de nombreuses fiches espèces (descriptions et illustrations), dont par exemple l’ensemble des arbres et arbustes indigènes ou plantés. (iii) Une auto-évaluation des connaissances avec exercices et quizz.

This curriculum offers students the opportunity to use the knowledge and skills they have learned across multiple disciplines to investigate and solve a local environmental issue. Interdisciplinary, project-based, inquiry focused, and highly adaptable, this curriculum will lead your students through the steps of making a difference in their community.

This open textbook is intended to expose students to the application of quantitative genetic models to plant breeding populations. Specific topics include conducting and interpreting multi-environment trials, resource allocation using engineering principles, genetic modeling of quantitative traits, simulation modeling, variance, covariance and heritability, prediction, selection, and genetic gain.

We use eigenvector-eigenvalue analysis to walk through a simple quasispecies model described in Bull, Meyers, and Lachmann, "Quasispecies made simple," PLoS Comp Biol, 1(6):e61 (2005). The dominance of a genotype depends, not merely on its ability to breed quickly (i.e. the rudimentary concept of survival of the fittest), but also on its ability to breed "true."

Proper management of uneven-aged interior Douglas-fir (Pseudotsuga menziesii var. glauca) stands is important for British Columbia’s central and southern interior. These stands constitute one of main components of the operable forest land in these areas, with easy access from main roads and towns. This study focused on the growth of uneven-aged Douglas-fir stands after pre-commercial thinning (spacing), with an impetus to improve upon current management practices. Data were collected from 24 permanent sample plots which were established near Williams Lake, British Columbia in 1989; thinning took place between 1990 and 1991. Three measurements have been made post-treatment: 1993, 1997 and 2004. The plot data were used to analyze different growth responses among three different spacing regimes (standard, 3 m clumped and 5 m clumped spacing) and a control. Analyses were performed at both the stand and tree level. The growth of basal area per ha, quadratic mean dbh, volume per ha and Lorey’s height were used for stand level analyses. At the tree level, dbh, height, basal area and volume were the variables of interest. At the stand level, mortality increased (7.1 to 107.1 stems/ha) and ingrowth decreased (2.4 to 8.6 stems/ha) for the second growth period (1997-2003), compared to the first growth period (5.8 to 107.1 stems/ha and 5.0 to 12.4 stems/ha, respectively). No significant differences in annual growth of quadratic mean dbh, basal area and volume per ha and Lorey’s height were noted between the different spacing regimes and the control. At the individual tree level, the 5 m clumped spacing regime usually had the highest dbh, basal area and volume growth for both growth periods. The one exception was for height growth, when analyzed using mixed-effects modeling, where no significant differences were found. Trees on the other two spacing regimes also had higher growth in dbh, basal area, and volume than trees on the control plots. The positive growth response to the spacing treatments at the single tree level was obtained without a reduction in growth at the stand level. This growth increase will result in the residual trees reaching larger sizes more quickly than they would have with no treatment, leading to improved mule deer winter range habitat and higher timber values.

Cretaceous and Tertiary strata exposed in northern Alaska record clastic sediment deposition within a foreland basin adjacent to the ancestral Brooks Range, and form part of an important petroleum play. The goal of this U.S. Geological Survey report is to synthesize the complex stratigraphy of this area into a more simplified scheme. It discusses the regional geology of northern Alaska and the stratigraphy of the Colville Basin in detail. Maps, cross sections, correlation charts, and numerous outcrop photos with detailed captions accompany the text.

A database of and access to journal articles and book chapters found useful by college and university science students; built from student work at Grinnell College, Grinnell, IA, USA. Used in science courses (especially Biology and Psychology courses) at Grinnell College.

This website was created by the GMO working group in the UConn College of Agriculture, Health and Natural Resources. We offer clear descriptions and explanations of a variety of issues related to genetically modified organisms, or GMOs. We hope you find the information useful, and we welcome your feedback. We thank Purdue Agriculture for inspiration, the format and assistance in building this site.

We think we know what trees are, but even at the level of genetics, it's difficult to find what separates them from other plants.

Professional definition example

This video features the remarkable discovery Jonathan made in 1998 about Basking sharks, the second largest fish on Earth. While diving with Basking sharks in the frigid waters of the Bay of Fundy, Jonathan saw parasitic lampreys on the backs of the sharks. This had never before been documented, so he returned the next year with a shark biologist and a lamprey biologist to attempt to recover living lampreys from the backs of Basking sharks. They didn't think Jonathan could do it. Wait until you see what happens! Please see the accompanying lesson plan for educational objectives, discussion points and classroom activities.

In the warm and blue waters off Hawaii, Oceanic White Tip sharks often follow behind pods of Pilot whales. For the longest time, biologists have had no idea what is going on. Are they eating the whales? Are they stealing food from the whales? In this video of an expedition to follow the sharks and observe them, Jonathan finally figured out what is going on, and you won‰ŰŞt believe the disgusting truth! Please see the accompanying study guide for educational objectives and discussion points.

This video features the Thresher shark, which may very well be the strangest looking shark in the world, with a tail almost as long as its body. This shark is very rare, almost never seen by divers...until now. Using advanced diving technology, Jonathan visits a remote reef in the Philippines where Thresher sharks show up every morning to be cleaned by small fish. Please see the accompanying study guide for educational objectives and discussion points.

In this video, filmed thirty miles off the coast of North Carolina, there is a shipwreck on the bottom, 130 feet down. Swarming around the wreck are dozens of Sand Tiger sharks. They look menacing, but they seem to be very docile. What are they all doing there, in one spot? That's what Jonathan wants to find out. Using a variety of filming techniques, Jonathan attempts to discover the secrets of the Sand Tiger shark gatherings at the wrecks, and does the first ever night dive with these shark..talk about scary! Please see the accompanying study guide for educational objectives and discussion points.

This resource contains three sets of lecture notes on soil health related topics:1) Soil Inorganic Properties and Soil Microbiology 2) Soil Fungi, Algae and Cyanobacteria3) Links Between Soil Health and Plant/Animal Health