Aging has been described as the predominant cause of vertical ridges on the fingernails. Onychorrhexis is the medical term used to describe longitudinal ridges on the nails that often accompany brittle nails. In contrast to longitudinal ridges, Beau's lines are horizontal or transverse depressions in the nail that may be confused with nail ridging.
Ruby-throated Hummingbird Migration. Ruby-throated Hummingbirds normally spend the winter in Central America. From March through May they migrate north, some through the eastern two thirds of Texas, some apparently through Cuba and Florida, and some apparently directly across the Gulf of Mexico. Birds reach the southern Gulf coast in late February and early March.
When Hummingbirds Migrate. Several factors affect hummingbird migration and when exactly these small birds set forth on their long journeys. The most important factor that determines the timing of hummingbird migration is daylight: the amount of daylight and the angle of the sun relative to the bird's location. As the light levels change seasonally, hummingbirds will purposefully eat more, increasing their weight by 25-40 percent through hyperphagia.