NOTES ON HOLE SIZE: 1  per Bergmann's rule, some species of birds may be larger in colder climates-e.g., a Canadian starling may be bigger than a Florida starling, thus the Canadian bird might not be able to fit in a certain hole size that its southern version could squeeze into.
A heart palpitation is the sensation that your heart has skipped a beat or added an extra beat. It may feel like your heart is racing, pounding, or fluttering. You may become overly aware of your heartbeat. This sensation can also be felt in the...
Many things can cause palpitations. You may have these feelings even when your heart is beating normally or somewhat faster than normal. Most palpitations are harmless and often go away on their own.However, some palpitations are signs of a heart problem. Sometimes the cause of palpitations can't be found. If you start having palpitations, see your doctor to have them checked.any things can cause palpitations. You may have these feelings even when your heart is beating normally or somewhat faster than normal. Most palpitations are harmless and often go away on their own.