Moist Dry environments. 1) Swimming sperm . (club moss, horsetails, ferns). 2) Airborne pollen swimming sperm . (few gymnosperms). 3)Airborne pollen . (gymnosperms & angiosperms). ID: 651494
DownloadNote - The PPT/PDF document "FLOWERS ! Land Plants Review" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Land Plants ReviewMoist Dry environments
1) Swimming sperm
(club moss, horsetails, ferns)
2) Airborne pollen + swimming sperm (few gymnosperms)3)Airborne pollen (gymnosperms & angiosperms)4) Animal borne pollen (angiosperms)Slide3
Brief History of Land Plants~470 MYA 1st Land Plants
300 MYA 500 species-club mosses, horsetails, ferns, gymnosperms
150 MYA 3,000 species mostly gymnosperms
90 MYA 22,500 species—mostly angiospermsToday 300,000 species—mostly angiospermsSlide4
5 STAGES OF LAND PLANT EVOLUTIONSlide5Slide6Slide7
5 STAGES OF LAND PLANT EVOLUTIONSlide8Slide9Slide10
5 STAGES OF LAND PLANT EVOLUTIONSlide11Slide12
5 STAGES OF LAND PLANT EVOLUTIONSlide13Slide14
5 STAGES OF LAND PLANT EVOLUTIONSlide15Slide16
What do you conclude from these data?
Why have angiosperms been so successful compared to gymnosperms?Slide17
Why have angiosperms been so successful?Adaptations to dry landRapid reproduction cycle & Early maturity
Well protected and well-nourished seedsEfficient seed dispersal mechanismsEfficient pollinationRecall the evolution of sperm transfer
But first animals on land were arthropods
insect fossils ~ 470
mya at the same time as the first land plants colonized land.First flying insects ~325 mya.
Major diversification of insects (bees, flies, butterflies & moths) ~150 mya occurred along with the radiation of flowering plantsSlide19
Phylum Angiosperms ( Flowering Plants)Two major classes
Types of Flowers
(Perfect Flowers)= flowers with all
of the usual male and female partsSlide21Slide22Slide23Slide24
Triploid Endosperm (3n)Slide25
Types of Flowers Cont’.Incomplete Flowers (Imperfect Flowers) =Flowers with one or more basic parts missing
have only female pistile.g. Staminate flowers have only male stamenSlide28
Corn with incomplete flowersSlide29
Flower SymmetryRadial Symmetry (Circular & disk-like)
Line through the center in any direction forms identical halves. (Attracts general pollinators)Slide30
Tallest FlowerHasRadial symmetry
Largest BlossomRafflesia arnoldiiSlide32
Flower SymmetryBilateral SymmetryLine through the center in one direction can produce mirror images.
Composite Flowers = Flowers grouped together into clusters to produce a showy displaySlide34
Head of a sunflowerSlide35
PollinationWind Pollination –earliest pollination Characteristics of wind pollinated flowers
Unisexual flowers—encourages outbreeding
= corn, oak, melonsDioecious= willows, poplars, maples, spinach, asparagusSlide36
Wind pollination in angiosperms (grasses)
Characteristics of wind pollinated flowers:
Large quantity of pollen producedSlide37
Animal PollinationMany types of animals involved:85% of flowers pollinated by insects (bees, butterflies, beetles, flies, ants); they get pollen and nectar.
Birds and a few small mammals especially bats
Less pollen needs to be produced than in wind pollination
Flowers are bisexual—increases efficiencySlide38
Generalist vs. Specialist StrategiesGeneralist
—attract many pollinators
Specialist—attracts only one pollinatorDisadvantage –flower and pollinator are dependent upon one anotherBenefit for plant—prevents waste of pollen & nectar for inefficient pollinationBenefit for pollinator—monopoly of food sourceSlide39
The Co-Evolution of Flowers and their PollinatorsSlide40
Attracting PollinatorsColor & UV & electric patternsNectar guides—lines of color that “guide” the pollinator to the nectaries (glands that produce the sugar water)Fragrance—scent glands
Bee FlowersFlowers open during dayBees visit many speciesSome flowers are specialized
only for beesSlide42
Some bee species grab tubular anthers & vibrate flight muscles and shake the pollen out of pore at
Ultraviolet Light Patterns
Ultraviolet Light Patterns
SexFlower that mimics female bees by color and scent to attract male bees.
Bird Flowers (e.g. hummingbird) Color red or orangeProduce lots of nectarFlowers large and shaped as tubes or funnels, cups or flasks.
Bat FlowersNocturnal flowersPale colorStrong scent
Bats with long
Nose and tongue. Some hover, some don’tSlide49
Fly FlowersFlies are second most common pollinatorsSmell is primary attractant
Color yellow, green, white, can be mottled and look & smell like rotting meatSlide50
Butterfly FlowersDiurnal Bright colorsSmell modest
into long tubes
Moth FlowersFlowers are nocturnalPale color
Strong sweet smell
Petals fused into long tubes for long proboscisSlide52
The case of the hawk moth and the irisSlide53
Hawkmoths & the S. African Iris
Hawkmoths are important pollinators!
S. African Iris produces nectar inside
a flower tube as a reward for pollinators.The ‘flower tube’ can vary in length.How does the Hawkmoth pollinate?...Slide54
How do hawkmoths pollinate S. African iris?
Hawkmoths stick their long
inside the flower tube to collect the nectar. When their tongue is inside, the the pollen from the stigma sticks to the head of the hawkmoth.When they visit a new flower, they
transfer the pollen from previous plant visits.
Distribution of flower tube lengthSlide56
Distribution of moth tongue lengthsSlide57
flower tube length
kind of selection do you think hawkmoth tongue length will have on flower tube length?Slide58