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.
Sometimes, a black eye can occur after cosmetic surgery to the face, such as a facelift or a nose operation. The area around the eye turns bluish or purple because tiny blood vessels under the skin burst and blood leaks out into surrounding soft tissue.
You can normally help reduce the symptoms of a black eye. Gently apply an ice pack to the skin around your eye as soon as possible after the injury. You can use a bag of frozen peas wrapped in a tea towel. The cold will numb the pain and relieve the swelling. During the first day, you should apply the ice pack to your eye for 15-20 minutes an hour every hour. Painkillers, such as paracetamol or ibuprofen, can be used to help relieve pain.