Hear the different songs of three lacewing flies in this interactive activity. These songs are an example of a reproductive barrier that can lead to speciation; the differences among the songs determine mate choice and result in reproductive isolation between the different populations.Also included is a table summarizing the different kinds of isolating mechanisms.ear the different songs of three lacewing flies in this interactive activity. These songs are an example of a reproductive barrier that can lead to speciation; the differences among the songs determine mate choice and result in reproductive isolation between the different populations.
Introduction. A black eye is bruising to the tissue under the skin surrounding your eye. It's usually caused by a blow to the face, such as a punch, or an accident such as a fall.
1 Dip a fresh clean cloth in hot water, squeeze it out and place it on the black eye. 2  This helps to remove the blood clots and enables easy blood flow. 3  This also helps to heal the bruising and blackening of the eye. 4  This process helps to heal the black eye within 5 to 7 days.