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Northern Movements

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  Dusky Shark (from Blueplanetarchive.com) A recent science paper noted Dusky Sharks feeding on Gray Seals off Cape Cod.  The Dusky Shark, Carcharhinus obscurus , is a subtropical to temperate species that roams further north during the warm months; it is not known to enter the icy northern waters north of the Gulf of Maine. Expectably, they tend to be rare north of the New England coast. That was then; this is now. We have already entered a new world of warming.  Dusky Sharks can grow to be quite large, reaching lengths of over 3 meters, or more than 10 feet. They are feeders on fish, lots of fish, and will, apparently, also go in for those nice succulent seals. Thisis not something they were thought to feed on much. However, those cheeseburgers dotting the coastline, hauling out on rocks, must be a pleasant sight for a hungry shark.  The abundance of seals makes them a central target for shark species. These marine mammals are abundant in late August all along the ...
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Much maligned Lamarck was one of the greats

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  His full name,  Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1 August 1744 – 18 December 1829), is not familiar to most people, they, those hoards of biology 101 students, just know him as Lamarck. Lamarck is best known to biology students as the guy who screwed up the mechanism for evolution in 1809. The use or disuse model, with the inheritance of aquired characters. A few points on this: First, this is how science is supposed to proceed. Ideas get proposed, and over time get solidified or thrown out.  As Francis Crick stated, most hypothesis are wrong. However, if they were not proposed than the wrongness would not have been determined. As Neil deGrasse Tyson has said,  The scientific method is doing its best to be wrong—until it's not . Lamarck did understand that organisms changed over time, that is that evolution occurred, long before most of his contempararies. We should remember Lamarck for his accomplishments, including his attempt at the ...
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Acadia forests: Everything is changing.

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    David Byrne had it wrong; it’s not the same as it ever was. Everything is changing.   The woods of Acadia National Park on Mount Desert Island are amazing. You can hike from a granite-topped bald hill into the trees and in seconds be enveloped in darkness. If you spend some time hiking around this isle of many trails, you will find differences in the forest. Besides the apparent change from woodlands to bald hill tops, the forested zone has some distinct clusters of tree species. There is the dark woodland of conifers, contrasted by the birch and aspen bunches.    Pre-European forests on Mount Desert Island (MDI) were dominated by the cold-adapted spruce-fir forests (Balsam Fir is typical along the Maine coast): these forests housed spruce grouse, red-backed voles, providing food and cover. The squirrels and chipmunks take advantage of the energy packed in the cone. While many bird species, such as the Blackburnian Warbler, Boreal Chickadee, and wrens, take ...
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Flatworm Fiesta

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In 2014, a giant discovery was made regarding the terrestrial planarians   Bipalium adventitium   and   B. kewense . Tetrodotoxin, a highly potent neurotoxin, was recorded in these species.  This marked the first instance of tetrodotoxin in terrestrial invertebrates, underscoring the potential danger these species pose. Tetrodotoxin had previously been found in many marine organisms, including the Blue-ringed octopus, and is named after its initial discovery in pufferfish species, which belong to the order Tetraodontiformes. The name of this order is due to the form of the beak, which looks like 4 (tetra), teeth (odont): Formes means shape.   These worms, known as shovel-headed garden worms or hammerhead worms, are predators of other worm species, such as earthworms. A  Bipalium  worm. Specific species are identified by their distinctive coloration, which often features colored bands and blotches. The one pictured here (stolen from thoughtco.com) has a...
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An Ancient Snorkeler

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Long before dinosaurs thundered across the land, before even the first fish dared to sprout fins, an unassuming yet extraordinary creature roamed the ancient seas. It was...   a snail.   Yochelcionella  (yo-kel-see-oh-nell-uh ) is a tiny, enigmatic mollusk from the Cambrian period, which ended about 485 million years ago. Its shell is adorned with a delightfully perplexing feature, a tubular snorkel-like extension near its peak. Paleontologists are debating its function. Was it an inhalant siphon drawing in fresh, oxygen-rich water? Or an exhalant tube expelling spent deoxygenated currents? Perhaps, in an elegant evolutionary flourish, it did both! No matter the answer, this humble creature is a key to the great puzzle of molluscan evolution.   Yochelcionella  greenlandica,  stolen from   Atkins & Peel, 2008. The Cambrian was   a period where evolution tried out a vast diversity of body plans. Imagine an ocean floor teeming with newly evo...
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