unit 2 seed dispersal how do seeds move from place to place? seed dispersal: unit 2
TRANSCRIPT
Unit 2
Seed dispersal
How do seeds movefrom place to place?
Seed dispersal: Unit 2
Where do ducks carry seeds?
Seed dispersal: Unit 2
Acorns:• How far do they fall from the
tree
http://www.arkive.org/pedunculate-oak/quercus-robur/video-09b.html
• Mammals and birds bury acorns to eat in the winter. What happens to the ones left in the ground?
http://www.arkive.org/pedunculate-oak/quercus-robur/video-11c.html
Gravity
Darwin’s ways of working: Unit 1Seed dispersal: Unit 2
Dandelion (Taraxacum officinale)
• What helps the seed to move?
“beautifully plumed seed”
Charles Darwin, On the Origin ofSpecies, 1859
http://www.arkive.org/common-dandelion/taraxacum-officinale-agg/video-09.html
• Can you think of other ways that make seeds light enough to be blown on the wind?
Wind
Darwin’s ways of working: Unit 1Seed dispersal: Unit 2
Seed dispersal: Unit 2
Sycamore(Acer pseudoplatanus)
• How tall is a fully grownSycamore tree?
http://www.arkive.org/sycamore/acer-pseudoplatanus/image-A6856.html
• Does each seed fall straightdown?
http://www.arkive.org/sycamore/acer-pseudoplatanus/video-09b.html
Gravity and wind
Seed dispersal: Unit 2
Common Poppy(Papaver rhoeas)
• Where does the seed come out?
• About how tall is a poppy flower?
• What could cause the stalk to sway?
• Why do you think each poppy plant can produce around 17,000 seeds?
Pepper Pot (sways on the stalk)
Blackberry(Rubus fruticosus)
• Which of these berries do you think will be eaten first?
http://www.arkive.org/harvest-mouse/micromys-minutus/video-08a.html
• What happens to the seed after the fruit has been eaten?
Animals - eating
Count the number of blackberries on this branch. Each one will have about 10 sections each with a seed. How many seeds are on this one branch?
Seed dispersal: Unit 2
Cleavers(Galium aparine)
• How do you think the fruits of cleavers move around?http://www.field-studies-council.org/urbaneco/urbaneco/introduction/colonisation.htm
• Which wild animals could do this?
Animals - clinging
Seed dispersal: Unit 2
Marsh marigold(Caltha palustris)
• Where do they live?
• What do you think will happen to the seeds when they fall out of the pod?
http://www.arkive.org/marsh-marigold/caltha-palustris/ image-A16924.html
Water
Seed dispersal: Unit 2
Sweet pea seed(Lathyrus odoratus)
• When will the seed podbe dry enough to suddenly explode and twist?
• Why do the seeds spray away from the Plant?
• How far can these seedstravel?
Explosive - springing apart
Seed dispersal: Unit 2
Squirting cucumber(Ecballium elaterium)
These plants live in hot drycountries. When drops of rain hit the ripe fruit they push off theplant squirting their seedsbehind them.
• Why is rain a helpful trigger?
Explosive - pushing forward
Seed dispersal: Unit 2
Here Darwin collected mud with lots of seeds in it
Keston Ponds
Seed dispersal: Unit 2
A duck inside and outside
Seed dispersal: Unit 2
Seed dispersal: Unit 2