Flowers are versatile, variable structures designed to facilitate pollination
        Pollination in pines = pollen is transferred from pollen cone to seed cone, by wind
      Pollination in flowering plants = pollen transferred from anther (microsporophyll) to
                stigma (megasporophyll), by several means

Pollinating agents (= whatever moves the pollen) include
      wind, insects, birds, bats, water, mammals

Flowers are often highly adapted to the pollinator
If the pollinator is an animal, the animal also sometimes is highly coadapted

Flower arrangement - to facilitate pollen transfer (= inflorescence) - see Figs. 19-7 and 19-8), textbook

Flower structure
        beetle flowers are fleshy, with deeply protected ovules, because beetles come to eat!
        wind pollinated flowers often lack a perianth
        ant-pollinated flowers often have reduced perianth and small,
                scattered nectaries  (nectaries = nectar-secreting glands)
        some orchids have elaborate mechanisms - traps, buckets, etc. -
                to make sure the pollinator follows the right path

Flower color
        bees see ultraviolet & yellow well, but can't see red - bumblebees are very attracted to blue 
        bat-pollinated flowers are large, white, bloom at night, are located far above ground, and have
               large pollen and nectar rewards

Flower symmetry (radial or bilateral)
        corolla shape often fits the shape of main pollinator(s)

Rewards - pollen and nectar
        pollen - high in lipids and proteins
        nectar - high in sugars (carbohydrates)
        a single flower isn't enough to satisfy the pollinator - must visit several to many flowers,
                which means the polllinator must carry pollen from flower to flower in order to get enough pollen for iteslf
        extrafloral [literally, outside the flower] nectaries sometimes attract insects close to flower buds,
                or may attract ants which protect the flower from herbivores

Scent/odor
        used as a cue by bees to help communicate location
        bat-pollinated flowers have penetrating scents
        beetle flowers often smell musty or yeasty
        some highly specialized pollinators try to copulate with flowers, because the flowers
                secrete the pollinator's sex pheromones and thus smell like a female insect
                        (pheromone = a substance given off by an individual that either attracts
                                or repels another member of the same species)
Blooming time
        bat-pollinated flowers usually bloom at night 
        bee-pollinated flowers are temperature-sensitive - don't open or secrete nectar
                if it's too cool, because the bees won't be active at cool temperatures 
        Sometimes flowers "train" animals to pollinate them, by appearing to open several days or even weeks before the anthers
                begin to shed pollen.  The animals form the habit of checking the flower every day, and when it finally opens,
                the animal is already there to pollinate the flower.

Thermogenesis
        some flowers produce heat -- temperature may be more than 10^o C higher than the surrounding environment
        insects are attracted to the heat and bring pollen with them, or
        flowers sometimes track (follow) the sun (e.g., sunflowers); the parabolic shape of the flower produces higher
        temperatures in the center of the flower, attracting insects and inducing them to linger

Pollinators also have special structures to facilitate pollination
        hairs and pollen baskets on bees' hind legs
        short feathers at base of hummingbird bills

There are some very exclusive pollinating echanisms
      Yucca moth - physically pollinates flower, then lays eggs in ovary of flower   -- you're not responsible for these details on the test
                            (Here's a short version of what happens - and here's more than you wanted to know)
      Fig wasps - wasps are imprisoned until poll``````````````````````````````````````````````````````````````````````````````````---++++++++++++
+-
-+

en is shed -- you're not responsible for details on the test
                            (Here again, is more than you wanted to know.  There is a bunch of extraneous
                            and even inappropriate material here, but the story of the fig wasps is included.!)
      Orchid bees - must collect scented material from several orchid flowers
                            in order to attract female bees to mate with - in the process of collecting
                            the scented material, they pollinate the orchid flowers.