From the Community: fish-mimicking octopuses, aquanauts and the evolution of ecology
An octopus that mimics toxic sea creatures, a plant’s chemical SOS when attacked by caterpillars, the genetic differences between ant social castes, unusually high records of jellyfish swarms this summer and Simon Levin discusses the evolution of ecology and where it is headed next. Here are stories in ecology wrapping up the month of August.
Fish-mimicking octopus: According to Jess McNally of Wired Science, “the Indonesian mimic octopus has the boldest defense strategy of any of its cephalopod cousins, and now scientists know how that strategy evolved” (see above). The findings, published in the September issue of Biological Journal of the Linnaean Society, revealed three key steps for the octopus’ mimicking behavior: switching to bold colors instead of camouflage , enhancing arm length and finally combining the bold colors and arm length to fine-tune their sea floor swimming, fish mimicking technique. Read more at “Octopus Evades Predators by Mimicking Toxic Sea Creatures.”
Tobacco caterpillars: Scientists have found that, when feasting on tobacco leaves, hornworm caterpillars signal predators. The caterpillar saliva mixed with the natural chemicals called green leaf volatiles released from the plant produces a distinct chemical call for the caterpillar’s natural predators, such as parasitic wasps or big-eyed bugs. As Ed Yong said on Not Exactly Rocket Science, “When hornworm caterpillars eat tobacco plants, they doom themselves with their own spit.” Read more at “Tobacco leaves emit warning chemicals that summon predators when mixed with caterpillar spit.”
Ant society: In a paper recently published in Science and reported on by Nature News, researchers compared the genome sequences of two ant species: Jerdon’s jumping ant Harpegnathos saltator and the carpenter ant Camponotus floridanus. As Alla Katsnelson reported, “ants of the same species but in different social castes have the same DNA sequence but assume radically different characteristics as a result of ‘epigenetic changes’ — DNA modifications that affect the expression of genes rather than the genes themselves.” Read more at “What does it mean to be an ant?”
Jellyfish swarm: Sarah Zeilinski of Surprising Science reported last week on an exceptionally high rate of jellyfish swarms this summer. She mentioned a Santa Cruz, California man who swam across Monterey Bay to raise awareness of ocean issues. “But then the ocean did a little awareness raising of its own. Thirty minutes into the swim, jellyfish—whose swelling numbers are considered by many to be a symptom of unhealthy seas—began to swarm,” wrote Zeilinski. He was stung all over his body by the jellyfish, including in his mouth. Read more at “A Jellyfish Summer.”
Evolution of ecology: At the beginning of August, Simon Levin—prominent ecologist and recent recipient of ESA’s Eminent Ecologist Award—crafted a Chronicle of Higher Education article exploring the history and projected evolution of ecology. As he concluded, “Ecology views biological systems as wholes, not as independent parts, while seeking to elucidate how the wholes emerge from and affect the parts. Increasingly, such a holistic perspective…has informed understanding and improved management of economic and financial systems, social systems, complex materials, and even physiology and medicine.” Read more at “The Evolution of Ecology.”
Also, evidence that a pitcher plant mosquito may have evolved due to climate change, researchers address the effects of war on wildlife, researchers map the Anthropocene, MIT scientists develop nanotechnology for oil spill mitigation, human excrement turned into alternative energy and aquanauts living on ocean floor prepare to surface.