Word: iridoid
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
Because checkerspots--a species which Bowers specializes in--feed on plants which contain secondary compounds called iridoid glycosoids, they are highly unpalatable to birds as well. These chemicals, Bower explains, may be toxic to some insects, but checkerspots have evolved mechanisms to excrete them quickly, sequester them in their exoskeleton or detoxify them. Thus the plant protects itself from most predators, and the butterflies render themselves "bitter" and in some cases nauseating. After feeding on members of these specialized species birds often throw...
...What I think is going on is that the caterpillars are storing the iridoid glycosids as they are feeding which is carried over their adult stage," Bowers explains. This summer, one of her projects will be to determine precisely what role the iridoid glycosoids--which are found in snapdragons and other plants, and may serve as a feeding stimulant for certain caterpillars--play in the unpalatability of the checkerspots...
Bowers also studies buckeye butterflies, a species native to California. Although buckeyes also feed on plants which contain iridoid glycosoids, unlike checkerspots they are not unpalatable. Brown, drab and cryptic, they also look very different from checkerspots which are brightly colored and tend to be gregarious...
...interested in whether or not the buckeyes differ from the checkerspots in their ability to sequester iridoid glycosoids from the plants that they feed on," Bowers animatedly explains. Her experiments this summer will focus on this problem First she will test the butterflies for the iridoid glycosoids, then examine how birds respond to pure iridoid glycosoids as opposed to the entire butterfly--both the checkerspots and the buckeye species...
Other aspects of Bower's research combine evolutionary, ecological and behavioral problems. "I'm going to start playing around this summer with a moth species that feeds on catalpa trees which contain large amounts of iridoid glycosoids," she says. The larvae of this species are gregarious and warningly colored but the adults are drab and cryptic. This type of life history suggests that the larvae are unpalatable but as they molt and become adults they are no longer unpalatable. "I don't exactly know what's going on with these guys, but I'm really psyched--it's really unusual...
| 1 |