White-Necked Jacobin (<em>Florisuga mellivora</em>) (IMAGE) University of Copenhagen - Faculty of Science Caption This is a white-necked Jacobin (Florisuga mellivora). Hummingbirds have the highest metabolic rate among all vertebrates, with a heart rate above 1,200 beats per minute, allowing them to hover in front of the flowers while beating their wings up to 200 times every second. Credit Jesper Sonne Usage Restrictions May be used when credited License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.