Flowers without petals: While walking the dog this summer, I tried to take note of all the flowers that are in bloom but which don't have petals. I took pictures of birch, oak, and hickory flowers; last summer I managed pictures of the willow flowers too (and with the help of some students labeled male and female plants along a trail.) The general belief is that the catkins that these plants have are probably, in many cases, examples of convergent evolution. Furthermore, all these flowering plants probably evolved from insect-pollinated ancestors. Wind-pollination is a derived characteristic in flowering plants, but an ancestral characteristic in gymnosperms. Mixed pollination system are probably more common than people realize & the paper below makes me want to keep an eye out for those mixed systems! (New word: ambophily)
Culley, T. M., S. G. Weller, A. K. Sakai. 2002. The evolution of wind pollination in angiosperms. TRENDS in Ecology & Evolution 17:361-369.
I had my daughter tap on the male cones of a gymnosperm in the cemetery while I tried to take a picture. You can kindof see the pollen poofing out.
Culley, T. M., S. G. Weller, A. K. Sakai. 2002. The evolution of wind pollination in angiosperms. TRENDS in Ecology & Evolution 17:361-369.
I had my daughter tap on the male cones of a gymnosperm in the cemetery while I tried to take a picture. You can kindof see the pollen poofing out.
The gymnosperms have been wind-pollinated for a long time! In flowering plants, wind pollination is more recent & has evolved repeatedly.
I hope your allergies aren't acting up.
The gymnosperms have been wind-pollinated for a long time! In flowering plants, wind pollination is more recent & has evolved repeatedly.
I hope your allergies aren't acting up.
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