plagues from a secular viewpoint-blood

The phenomenon of red tide has been around since ancient times. Some biblical scholars believe the seventh chapter of Exodus mentions red tide when the river Nile turns to “a river of blood,” where many fish were killed and the people could not drink the water. The red tide is a harmful agal bloom of dinoflagellates. The growth and persistence of an algal bloom depends on wind direction and strength, temperature, nutrients, and salinity.[1] Red tide species can be found in oceans, bays, and estuaries, but they cannot thrive in freshwater environments.[2][1] Certain species of phytoplankton and dinoflagellates like 'Gonyaulax' found in red tides contain photosynthetic pigments that vary in color from brown to red. These organisms undergo such rapid multiplication that they make the sea appear red. When the algae are present in high concentrations, the water may appear to be discolored or murky. The most conspicuous effects of red tides are the associated wildlife mortalities and harmful human exposure. The production of natural toxins such as brevetoxins and ichthyotoxins are harmful to marine life.[3] Effects of red tides can worsen locally due to wind driven Langmuir circulation and their biological effects

This addendum to the algae theory points out that, for red algae to flourish in the first place, there needs to be slow, sludgy, warm water. In 2010, research on stalagmites —elongated mineral deposits that form out of calcium in precipitation — suggested that there had been a dry period towards the end of the rule of Pharaoh Ramses II. That change would have dried up the Nile and significantly slowed down the flow of water, according to paleoclimatologist Augusto Mangini. These conditions are ripe for the growth of the bacterium Oscillatoria rubescens, more colloquially, Burgundy Blood algae, according to biologist Stephan Pflugmacher.

Another possibility was that there was a seasonal flood upstream and the red oxide in the silt tainted the river. The excessive silt clogged the gills and fish suffocated.


haggadah Section: -- Ten Plagues