My elementary school music teacher, Ursula Fecheck, always selected seasonal pieces for us to sing. I remember Skin and Bones in fall, and the Cuckoo Song come spring. I wonder what Ms. Fecheck would have suggested to accompany our first hard frost of autumn.
In this light, I believe it is important that we all know of the recent recommendation of the IPCC (Intergovernmental Panel on Climate Change). Limiting global warming to 1.5ºC would require rapid, far-reaching and unprecedented changes in all aspects of society, the IPCC said in a new assessment. With clear benefits to people and natural ecosystems, limiting global warming to 1.5ºC compared to 2ºC could go hand in hand with ensuring a more sustainable and equitable society, the Intergovernmental Panel on Climate Change (IPCC) said on Monday. “One of the key messages that comes out very strongly from this report is that we are already seeing the consequences of 1°C of global warming through more extreme weather, rising sea levels and diminishing Arctic sea ice, among other changes,” said Panmao Zhai, Co-Chair of IPCC Working Group I. The report highlights a number of climate change impacts that could be avoided by limiting global warming to 1.5ºC compared to 2ºC, or more. For instance, by 2100, global sea level rise would be 10 cm lower with global warming of 1.5°C compared with 2°C. The likelihood of an Arctic Ocean free of sea ice in summer would be once per century with global warming of 1.5°C, compared with at least once per decade with 2°C. Coral reefs would decline by 70-90 percent with global warming of 1.5°C, whereas virtually all (> 99 percent) would be lost with 2ºC. “Every extra bit of warming matters, especially since warming of 1.5ºC or higher increases the risk associated with long-lasting or irreversible changes, such as the loss of some ecosystems,” said Hans-Otto Pörtner, Co-Chair of IPCC Working Group II. Limiting global warming would also give people and ecosystems more room to adapt and remain below relevant risk thresholds, added Pörtner.
Araucarioxylon arizonicum (the state fossil of Arizona) is an extinct conifer of the late Triassic, a time when what is now Petrified Forest National Park was a low, near equatorial, plain. Mountain streams, flowing to the sea, carried volcanic ash high in silicon bound as orthosilicic acid and as crystals of silicon dioxide, quartz. Trees deposited in rivers were covered in sediment, their tissues were saturated, and tubes of xylem and phloem provided easy access to deep within the plant. The rest is history. Negatively charged crystals of quartz accumulated in cells and cast organic tissue in rock – preserving specimens in minute detail. The colors in petrified wood are dependent upon mineral ions bound to quartz. Below, relatively pure quartz is white, iron oxides may be responsible for reds and browns, and manganese may be associated with hues of pink and orange.
Some think that places such as this are slippery, smelly or, worst yet, dirty. I agree with the first, for marine macrophytic algae produce quantities of mucus to, in part, mitigate the effects of desiccation and temperature extremes. But surely tide pools are neither smelly nor dirty. When the tide is out, these places provide refugia for algae and animals with little or no capacity to withstand the rigors of exposure to the air. They provide windows of opportunity to commune with a rich community of invertebrates that live in the marine inter-tidal. One can see crabs (and a variety of other crustaceans), periwinkles, whelks, chitons, mussels, urchins, starfish, brittle stars, anemones, hydroids, sponges, bryozoa, and even tunicates, going about the business of finding food and make more of their own. I have admired tide pools since I was a kid. I will admire them always. I will explore them as long as I am able to negotiate the slippery substrates they present.
I first thought of Wiwaxia. But, it could not be. Although Wiwaxia and this animal are approximately the same size, the former lived nearly 500 million years ago and paleontologists have not yet been able to determine whether it was an Annelid or a Mollusc. This animal is surely an Arthropod, the caterpillar of Acronicta americana, the American Dagger Moth.
A decayed Birch had given way and toppled into the water. I recovered what I could and a chainsaw worked the remainder. As I collected the shorts, I noticed that one bore the graze marks of a snail. Many gastropods use a toothed rasp to gather food. Grazing is highly ordered and elaborate patterns may accumulate on appropriate substrate. Look closely at any one of approximately fifty arcs of activity. More than a dozen feeding strokes are taken to the left, the animal moves forward, and as many strokes are then taken to the right. The behavior is reminiscent of what a cow might do on pasture … munch, munch, munch to the left, a step or two forward, and munch, munch, munch to the right.
Opportunities to use the word aposematism do not present themselves often. Today, however, it is warranted because Monarchs provide a textbook example of the phenomenon of warning coloration. The bold stripes are a clear signal to predators to stay away. And, for good reason. The primary food of this instar is Milkweed, a plant which contains cardiac glycosides, compounds which are highly toxic. The pharmacodynamics of glycosides, especially the cardenolide steroids, are widely known. Digitalis or digoxin, perhaps the best known of these compounds, is derived from Foxglove. In humans, the compound increases the force of heart muscle contraction and reduces heart rate. It has been used, clinically, as an antiarrhythmic. Such agents are therapeutic at low doses and can be lethal at higher ones.
Arion subfuscus is common and may be found when conditions are wet and, especially, in the early morning. Slugs are snails. Like other gastropod molluscs they have a shell but theirs is carried internally and has been reduced to just a sliver. Like other land snails, Arion has a pneumostome which allows air to reach the lung. In this image you can see a hint of this feature if you look a third the way down the right side of the mantle (the oval structure which leads from the base of the optic tentacles). I think this is a very pretty animal indeed.