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...
Heart Palpitation: 8 Reasons for Your Abnormal Heartbeat. Heart palpitations occur when the heart beat increasesâit may noting a flutter, skipped beat, or heart rate thatâs abnormally hard and fast in your chest, throat, or neck. Heart palpitations can be frightening if youâve never experienced them before.