noctural
dr. dolittle | September 21, 2015 By Taken by fir0002 | flagstaffotos.com.au Canon 20D + Canon 70-200mm f/2.8 L (Own work) [GFDL 1.2 (http://www.gnu.org/licenses/old-licenses/fdl-1.2.html)], via Wikimedia Commons
Researchers at the University of Vienna are studying vocalizations from giraffes. They captured recordings of the animals "humming" during the night at local zoos. Zookeepers were surprised to learn the animals made such noises as they are not heard during the day. Researcher Dr. Angela Stöger remarked to the New Scientist, "I was fascinated, because these signals have a very interesting sound and have a complex…