Our planet, Earth, has had variations in the amount and location of sunlight falling upon it since it began swirling around the sun at the beginning of our solar system. Early life forms probably needed to live in tropical conditions where the climate was pretty constant and water was a liquid all of the time.
Once life got a toe-hold here bacteria, plants and critters of all sorts began adapting to survive in places different from the one they were currently living in to take advantage of new resources and lack of competition, even if the climatic conditions weren’t as uniform as life in the tropical regions. These organisms slowly developed adaptations to allow them to survive in drier conditions, colder conditions, darker conditions, and wildly varying conditions caused by the changing seasons until we have the rich crazy quilt of life we see around us now. Fortunately for us the seasons are more or less predictable and serve as a natural calendar to which everything from plants to people have adapted. All life on earth, whether aware of it or not, follows these cycles that have come to rely on them. As Pete Seeger (borrowing from Ecclesiastes) wrote,
To Everything (Turn, Turn, Turn)
There is a season (Turn, Turn, Turn)
And a time to every purpose, under Heaven.
Today this natural calendar is called a “Phenology.” and is one of the tools landscape designers spend a lot of time studying (and worrying about!) in order to provide our clients with landscapes that have that vaunted “four season interest.”
Phenology is the study of periodic plant and animal life cycle events and how these are influenced by seasonal and interannual variations in climate. The word is derived from the Greek phainomai ( to appear, come into view) and indicates that phenology has been principally concerned with the dates of first occurrence of biological events in their annual cycle. Examples include the date of emergence of leaves and flowers, the first flight of butterflies and the first appearance of migratory birds, the date of leaf colouring and fall in deciduous trees, the dates of egg-laying of birds and amphibia, or the timing of the developmental cycles of temperate-zone honey bee colonies. In the scientific literature on ecology, the term is used more generally to indicate the time frame for any seasonal biological phenomena, including the dates of last appearance (e.g., the seasonal phenology of a species may be from April through September).
Because many such phenomena are very sensitive to small variations in climate, especially to temperature, phenological records can be a useful proxy for temperature in historical climatology, especially in the study of climate change and global warming. For example, viticultural records of grape harvests in Europe have been used to reconstruct a record of summer growing season temperatures going back more than 500 years. In addition to providing a longer historical baseline than instrumental measurements, phenological observations also provides high temporal resolution of ongoing changes related to global warming.
From Wikipedia, the free encyclopedia
Follow the links below to phenology studies being done by “citizen scientists” in North America and Europe. Lots of great photography and information!
