From Seed to Seed:
Plant Science for K-8 Educators

Theories of evolution

You now know that the members of the plant kingdom exhibit an enormous diversity of form. Plants have colonized almost every corner of the earth-including some of the most hostile environments-from the coldest of arctic environments to the driest of deserts. Consider the desert, for a moment, with perhaps a few cacti and other succulents enduring the relentless sun and drying winds. All deserts get at least some rainfall, and after a rainstorm, the desert literally comes alive, with a flush of wildflowers and other native plants in a hurry to make use of that rain, to grow and reproduce before the heat and drought return.

Many plants have an amazing, almost uncanny, ability to remain in a dormant state until favorable conditions arise-and then react quickly to take advantage of those conditions when they do arrive. Some seeds, for example, can pass unharmed through the digestive tracts of birds, to eventually be deposited, fertilizer and all. And many fruit trees must undergo a certain amount of chilling before they'll break dormancy in the spring.

Plants are some of the first organisms to colonize ravaged landscapes-witness the tenacity of plants colonizing sterile lava fields after a volcanic eruption. Student gardeners will soon know all too well about some plants' ability to survive, as they struggle to control the weeds intent on taking over their garden. Next time they pull a weed, have them consider for a moment the wonder of a plant that can so quickly reclaim a recently weeded bed!