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o why are these lakes pink anyway? It's been a mystery for some years, but the puzzle's finally been cracked. Scientists found that pink bodies of water like Lake Hillier contain both Halobacteria and a type of algae known as Dunaliella salina, which thrive in salty environments like the pink lakes. The carotenoid red pigments secreted by Halobacteria and d. salina are responsible for the pink lakes' otherworldly colors. These same algae also flourish in the Dead Sea.

As benign as it may look up close, the tiny seaweed Caulerpa taxifolia can wreak quite a bit of havoc on coastal ecosystems. This super algae is very adaptable; it also grows fast and spreads easily. Eric Noel Muñoz gives the details of this plant's incredible invasion, shedding light on the risks of introducing invasive species into new ecosystems.

A decade-old technique that allows researchers to control brain function in lab animals could partially restore sight to the blind. In a trial sponsored by RetroSense Therapeutics, a startup company in Ann Arbor, Michigan, doctors will inject a harmless virus loaded with DNA from photoreceptive algae into the eyes of 15 patients suffering from retinitis pigmentosa. The experimental procedure represents the first human test of optogenetics, which is a technique that genetically modifies neurons to make them responsive to light. Doctors from the Retina Foundation of the Southwest will perform the procedure, and attempt to transfer the job duties of photoreceptor cells to different cells in the eye to restore sight.

This interrupted case study, designed for an introductory biology or environmental science course, introduces students to the complexity of ecosystems by examining changes in trophic interactions and abiotic factors in a freshwater ecosystem as a result of human actions. The case narrative describes the recent and undesirable appearance of decomposing algae (Cladophora glomerata) on a public beach in the Laurentian Great Lakes. Students are asked to use the scientific method by creating hypotheses and examining observational data to describe biotic and abiotic components of the Great Lakes ecosystem. The case requires students to differentiate between benthic and pelagic environments (e.g., the influence of depth and phytoplankton density on light availability, and the availability of phosphorus) and the interactions between organisms in both environments. Students also examine shifts in these interactions as a result of the newly introduced zebra and quagga mussels, which have ultimately resulted in the algae's presence on the beach. There are also opportunities to discuss the impact of these ecosystem changes on people who own property and/or visit the beach.

Learn the fundamental concepts behind renewable energy sources and energy efficiency through these short videos.