Nature World News: Fewer cold snaps in Florida are helping mangroves extend their territory, according to a new study. Mangroves thrive in warm, salty areas and are known to form complex ecosystems. Their presence in the Sunshine State was limited due to freezing temperatures during winter. However, from the past few years, there has been a decline in the number of days that see temperatures dipping below negative 4 degrees Celsius (25 degrees Fahrenheit). Fewer cold days have led mangroves to getting a foothold...