EPOW - Ecology Picture of the Week

Scarlet Gilia (Gilia aggregata, a.k.a. Ipomopsis aggregata), 
Family Polemoniaceae (Phlox)
Eastern Oregon, USA

Explanation:   From the river bottomlands of eastern Oregon comes this beautiful bloom of Scarlet Gilia.  It is also called Skyrocket, Scarlet Trumpet Flower, Sky Trumpet, and other common names, and has had a diversity of scientific names as well.  

Native Americans used the plant to make a tea to treat colds, blood conditions, and gonorrhea, and to produce glue and a blue dye from the roots.  

This is a biennial or perennial that produces red tubular flowers ("sympetalous corolla") which are pollinated by hummingbirds, especially Calliope Hummingbirds in eastern Oregon and Rufous Hummingbird and Broad-tailed Hummingbird in Arizona, and also by the White-lined Sphinx, a species of hawkmoth.  

However, there are some "nectar thieves" -- nectar-robbing bumblebees (Bombus occidentalis) -- that thwart these pollination services.  

Individual Scarlet Gilia plants may live 1-8 years, then only once will produce a stalk of flowers and then dies.  But wait, nature isn't that simple...

A recent study on Scarlet Gilia in northern Arizona has determined that the plant actually "benefits" from direct effects of being browsed upon by ungulate herbivores, mainly mule deer and elk.  The benefits take the form of increasing the plant's genetic fitness.  Browsing of the flowering stalk (the "inflorescence," in botanical terms) causes the plant to regrow and produce 5 new flowering stalks and actually double its flower and fruit production.  

Moreover, after the plant has been initially browsed, when it regrows it apparently changes its chemical constitution to be less palatable to further browsing, so it can then complete its flowering and reproductive cycle.  Browsing causes the plant to produce cucurbitacins, which are triterpenes that are bitter and toxic to browsing animals.   

So here is an unassuming little plant that has apparently co-evolved not just with its hummingbird and moth pollinators -- and has put up with nectar thieves that serve no pollination benefit -- but has also co-evolved with potentially destructive, large mammalian browsers ... taking advantage of the "key ecological functions" of pollination and browsing of those wildlife species to increase its own fitness.  And you thought this was just a pretty flower.  Nature is amazing!