Phenology is the study of periodic plant and animal life cycle events and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors (such as elevation). The word is derived from the Greek φαίνω (phainō), “to show, to bring to light, make to appear” + λόγος (logos), amongst others “study, discourse, reasoning”
I missed a week (two?) of posts because of being busy with the mushroom logs. Then when I started this post about one word – phenology – it took on a life of its own and went down several tributaries. But here it is at last.
The scientific world has been all abuzz about phenology for some time now, because the warmer climate is causing big changes in how early plants flower, when birds and butterflies migrate, and other appearances on the landscape. What’s the big deal?
Plants are a source of pollen and nectar for insects and hummingbirds, among others. Migratory species in particular time their movements based on available food along their routes and at their destinations. This is critical for survival.
You may have heard about the issues that monarch butterflies are having, what with habitat destruction, (in their overwintering areas, and along migration routes) and most recently, large areas of genetically modified crops that allow “weed” control on a scale previously impossible. Monarch caterpillars specialize on milkweed, a native plant that is considered expendable on corporate farms, and now almost completely destroyed by greatly increased use of Roundup herbicide.
But back to phenology: If plants flower before their pollinators arrive, the species don’t interact as they have evolved to. However, the arrival of birds and also their expanding ranges indicate that they and other species are probably adapting to changing availability of food resources – the complicated dance of adaptation and survival has been going on for aeons, after all. The difference now is how fast change is taking place, and how many species will get left out in the process. Accelerated change is the result of global climate change caused by humans. So much so, that there is a new word coined to describe the era that we now live in: the Anthropocene. It is hypothesized that it will be the era of the sixth great mass extinction. Here are top-notch podcasts about the topic from a group of nerdy science grads who can really communicate and entertain.
Here in Gopher Valley, I started taking photos of plants in bloom, and this year I thought to compare the bloom time for one or two. There is nothing like a photo to cut to the important features and make connections. As we all know, year to year variation is normal, so this isn’t a scientific study. However, over long periods of time, the signal or trends show up, and that is when it gets really interesting.
One of the most interesting aspects of adaptation is that species change at their own rates, so you don’t see whole groups or ecosystems changing simultaneously and marking north together across the landscape. Plants (and animals) form unique new assemblages as conditions change. This is well documented in the literature of post-glacial vegetation by many authors. This time, in the Anthropocene however, things will be even more complicated because human agriculture and habitation is blocking migration corridors, leading some to advocate for a controversial method of conservation called assisted migration.
As you look at my examples of phenology, and after you listen to the podcasts and poke around the links above, check out some long-term phenological studies that really say something about what is happening in the natural world. Here’s one to get you started.