The value of nutrition and exercise, according to a moth

Researchers discover the secret behind the astonishing feats of nectar-feeding animals

Date: February 22, 2017

Source: University of Arizona

Quick! Name the top-performing athletes in the animal kingdom. Cheetah? Try again. Blue whale? Nope.

Here's a clue: If you take a walk in the desert on a moonlit night, you might see them, darting from flower to flower and hovering in midair: moths of the hawkmoth family (Sphingidae).

Nectar-feeding moths, pollinating bats and hummingbirds are masters in sustaining the most intense exercise of all animals. To extract nectar from a flower, they must hover in front of the flower before darting off to the next one. But how can these organisms perform such feats on a diet that's mostly sugar?

New research by University of Arizona biologists not only offers an explanation, but also suggests that these animals stay healthy not despite, but because of, their sugary diet.

Oxygen, while necessary for life to exist, is a double-edged sword. The more we engage in intense aerobic exercise, such as hovering, the more oxygen reveals its ugly side in the form of reactive oxygen species -- small reactive molecules that wreak havoc on cells.

Researchers in the lab of Goggy Davidowitz in the Department of Entomology in the UA's College of Agriculture and Life Sciences discovered that hawkmoths (also known as Manduca moths) have evolved a strategy that helps them minimize the muscle damage inflicted by the oxidative stress generated during sustained flight. The results are published in the journal Science.

Continued 

Insect-Eating Bat Outperforms Nectar Specialist as Pollinator of Cactus Flowers

Dec. 6, 2012 — Of the two bat species known to visit the flowers of the cardon cactus in Baja California, one depends entirely on nectar and is highly specialized to feed from the flowers, which are adapted for pollination by bats. The other is an insect-eating bat best known for its ability to hear the footsteps of large insects and scorpions and capture them on the ground.

In a surprising result, scientists at the University of California, Santa Cruz, have found that the insect-eating pallid bat is a more effective pollinator of the cactus flowers than the nectar-feeding specialist, the lesser long-nosed bat.

"The lesser long-nosed bat is highly specialized for nectar-feeding and was thought to be the primary pollinator of the cardon cactus. But when we measured their effectiveness, we found that the pallid bat actually delivers about 13 times as much pollen per visit," said Winifred Frick, a research scientist at UC Santa Cruz. Frick is first author of a paper on the new findings published online in American Naturalist.

The study highlights the complex nature of the mutually beneficial relationships between plants and their pollinators, which in most cases have evolved together over long periods of time. There are often conflicts of interest between the partners, according to coauthor Kathleen Kay, assistant professor of ecology and evolutionary biology at UC Santa Cruz.

Continued:  http://www.sciencedaily.com/releases/2012/12/121206131827.htm