To be alert is to be in a vigilant state of watchfulness; to be wide awake and aware of what is going on around you.
To listen is to give attention to sound or action; to listen to what one is saying and try to understand.
Lately on my walks, especially at dawn or dusk, I see Cottontail rabbits running about. If they hear the slightest noise they always respond the same: lifting their head to pause, and listen intently. These rabbits seek out habitats that sit on the fringes of open spaces. So many of the people I see pausing to really listen with a goal to understand different perspectives, seek out a similar habitat: one that facilitates an open dialogue, with a heart to understand or bring understanding, not to win an argument. Though often seemingly on the fringes of the extreme majority because of their ability to be quick to listen and slow to speak, this is what we greatly need.