The Essential Rhythm | WERU 89.9 FM Blue Hill, Maine Local News and Public Affairs Archives

Producer/Host: Sarah O’Malley This episode answers listeners’ questions about estuaries, the zone in a river where it meets the sea. The influence of tidal flows and differing densities of water are discussed relative to the mixing of fresh and salt water. Organisms that can live in the wide range of salinities typically found in estuaries are briefly discussed.  About t...

Producer/Host: Sarah O’Malley This episode explains where the salt in the ocean comes from, and outlines in simple terms the balance of inputs and outputs that result in relatively steady state salinity in ocean water. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. S...

Producer/Host: Sarah O’Malley This episode describes the history of the northwest Atlantic/Canadian maritime population of walruses, including their historic range and reasons for extinction. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. She teaches biology and sust...

Producer/Host: Sarah O’Malley This episodes describes the unique ocean going fish Mola mola. It includes a physical description, behavioral characteristics and how to differentiate the fin of a Mola mola from that of a shark.  About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experienc...

Producer/Host: Sarah O’Malley This episode explains the origins of the sandy beaches of maritime Canada, as related to the erosion of sandstone formed as a result of the erosion of the ancestral Appalachian mountains. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. Sh...

Producer/Host: Sarah O’Malley This episode describes the ecological of horseshoe crabs as species that transfer energy to many different threads in the food web, including migratory shore birds and fish. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. She teaches...

Producer/Host: Sarah O’Malley This episode explains why horseshoe crabs’ blood is blue as well as the critically important substance found in it. Limulus amoebocyte lysate is isolated from horseshoe crab blood and used to test the sterility of medical equipment and vaccines, and as of yet has no approved synthetic alternative in the United States. About the host: Sarah O’Malley i...

Producer/Host: Sarah O’Malley This episode describes the state of horseshoe crab populations as well as the challenges to understanding population levels in the absence of data.  About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. She teaches biology and sustainabili...

Producer/Host: Sarah O’Malley This episode describes some key anatomical features of Limulus polyphemus, American horseshoe crabs and explains the mating behaviors that can be seen when the animals visit the intertidal zone. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the...

Producer/Host: Sarah O’Malley This episode summarizes the findings of Johnston et al (2023) showing that commercial rockweed harvest as practiced in Maine results in on average reduced height but pre harvest levels of biomass one year post harvest. Different implications based on management perspectives are noted.  Johnston, Elliot et al 2023 Bed-scale impact and recovery of a comm...

Producer/Host: Sarah O’Malley This episode describes the process of using environmental DNA (eDNA) to investigate the presence or absence of organisms in the environment.  About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. She teaches biology and sustainability...

Producer/Host: Sarah O’Malley This episode describes the concept of life history strategy, and highlights findings from a paper that investigated the impact of introduced intertidal crabs (Carcinus maenus, European green crabs and Hemigrapsus sanguineus, Asian shore crabs) on Atlantic rock crabs (Cancer irroratus). The study demonstrated that the rock crab life history strategy of...

Producer/Host: Sarah O’Malley This episode summarizes a 2019 study on the interactions of European green crabs and Asian shore crabs. Researchers found that in rocky intertidal habitats on the southern New England, when shore crabs and green crabs overlap, green crab density goes down significantly. They identified key behavioral differences between juveniles of the two crab species tha...

Producer/Host: Sarah O’Malley This episode highlights Calanus finmarchicus, a tiny crustacean that serves as a keystone species in north Atlantic food webs. North Atlantic Right Whales, commercially important fish and virtually all other predators in the north Atlantic feed on it because of its high nutrient content. C. finmarchicus likewise feeds heavily on phytoplankton and is a major cond...

Producer/Host: Sarah O’Malley This episode describes a little known intertidal snail that feeds on kelp, the Lacuna snail (Lacuna vincta). The snail can also be found by searching out its doughnut shaped egg masses on kelp fronds. Its hard times dispersal strategy involves creating a mucous parachute which enables it to drift away on water currents. About the host: Sarah O’Malley is an...

Producer/Host: Sarah O’Malley This episode discusses misconceptions about early animal evolution, including the notion that resolving early animal evolution will settle the debate as to whether our earliest ancestors were sponges or comb jellies. Both groups of animals display a suite of undervalued traits, referred to as hidden biology, that demonstrate their evolutionary complexity. Refere...

Producer/Host: Sarah O’Malley This episode describes the ‘ciliary mucus particle transport’ mechanism that many animals use for feeding. Reef building corals are the primary example featured in this show. Suspension feeding Molluscs are also included as an example of independent evolution of this trait (two or more lineages landing on the same trait independently). About the host...

Producer/Host: Sarah O’Malley This episode explains the chemical structure of mucus, and revisits is role in early animal evolution as well as as a lubricant for animal movement and travel. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. She teaches biology and sustai...

Producer/Host: Sarah O’Malley This episode discusses the origins of mucus in early animal lineages, including Cnidaria and Ctenophora, and highlights the lack of mucus in another early animal lineage, Porifera (sponges). Scientists hypothesize that the invention of mucus was a major event that enabled the evolution of true tissues, as well as serving as the front line of the immune system, s...

Producer/Host: Sarah O’Malley This episode continues the discussion of the role of shells in marine invertebrates, including protection from predation and the environment. Like vertebrate skeletons, invertebrate shells also provide attachment points for muscles and enable complex movement. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate ab...

Producer/Host: Sarah O’Malley This episode describes some of the similarities between vertebrate bones and mollusc shells. The use of calcium to make the different mineral components, as well as the different layers of mollusc shells is discussed. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experien...

Producer/Host: Sarah O’Malley This episode discusses physical factors that influence food availability and thus seasonal rhythms at the sea shore. Soft shell clams (Mya arenaria) are used to illustrate the seasonal connections between temperature, food and reproduction About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her lis...

Producer/Host: Sarah O’Malley This episode describes the scientific process, as executed by a group of first year college students surveying the intertidal zone in Maine. Findings include a generally positive relationship between the distance from the high tide line and biodiversity, as well as an unexpected pattern of periwinkle abundance relative to time of day. About the host: Sarah O&#82...

Producer/Host: Sarah O’Malley This episode explains the function of the CO1 gene, which is used for DNA barcoding animals. The gene codes for part of the protein cytochrome oxidase, which is integral to aerobic respiration and the generation of ATP. It is also idea for barcoding because of its not to fast/not too slow mutation rate. About the host: Sarah O’Malley is an ecologist, natur...

Producer/Host: Sarah O’Malley This episode describes the results of DNA barcoding a barnacle, and explains the characteristics scientists use to classify barnacles as an arthropod, related to shrimp and lobsters. About the host: Sarah O’Malley is an ecologist, naturalist and science communicator passionate about deepening her listeners’ experiences with the natural world. She tea...