Search results
Results from the WOW.Com Content Network
COVID-19 symptoms range from asymptomatic to deadly, but most commonly include fever, sore throat, nocturnal cough, and fatigue. Transmission of the virus is often through airborne particles . Mutations have produced many strains (variants) with varying degrees of infectivity and virulence . [ 9 ]
NOVA explores the mysterious ecosystem of the desert: a snowstorm; a lashing summer monsoon; and the emergence—in a pool created only minutes before—of a pair of adult spadefoot toads. Toads who had been waiting beneath the sand for a year for this brief and fortuitous moment to procreate the next generation. Narrated by Robert Dryden.