Flowers with 1 petal (very rare)
White Calla Lily
Lilies have 6 petals;
Fusing of petals
Flowers with 2 petals (very rare)
Euphobia
Flowers with 2 petals (very rare)
Can still be
found in
Singapore:
photo taken
outside a
HDB flat
Flowers with 3 petals (quite rare)
Waterplantain
Trillium
Flowers with 5 petals (very common)
Hibiscus
Taken in Singapore
Bougainvillea: which one is the flower?
Pink ‘flower’: 3
bracts or modified
leaves;
light-yellowish flower
in centre has 5 petals;
actually there are 3
flowers in centre
Columbine: How many petals?
5 petals & 5 sepals
(modified petals)
Most of the times,
sepals look exactly
like petals
Daffodil: How many petals?
3 petals & 3 sepals
(modified petals)
Flowers with 8 petals (quite rare)
Bloodroot
Yellow Moonbeam
Coreopsis
Daisies with 13 petals (quite rare)
Black-eyed Susan
Orange Zinnia
Daisies with 21 petals (quite rare)
Shasta Daisy
‘Petals’ are bracts
or modified leaves;
100-200 flowers in
centre;
Composite Flower
Daisies with 34 petals (quite rare)
Field Daisy
White Daisy
Flowers with 34 petals (quite rare)
Sunflower
‘Petals’ are bracts
or modified leaves;
100-200 flowers in
centre;
Composite Flower
Exceptions
Ixora
Daylily
Exceptions
Starflower
Passion Flower
Exception Type 1
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Some flowers follow Lucas Sequence:
2, 1, 3, 4, 7, 11, 18, 29, …
Like Fibonacci sequence except first 2
terms are 2 and 1, instead of 1 and 1
Fibonacci: 1, 1, 2, 3, 5, 8, 13, 21, 34, …
E.g. 4 petals and 7 petals
Flowers with 4 petals
Ixora: Taken in
Singapore
Flowers with 7 petals
Starflower
Exception Type 2
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Doubling of the petals: e.g. from 3 to 6
petals; from 5 to 10 petals
Flowers with 6 petals
Daylily
3 petals & 3 sepals
We just use layman’s
term: 6 petals. Why?
Or else problem with
daisies and sunflower
Flowers with 6 petals
Iris
3 petals & 3 sepals
Orchid: 6 petals
Singapore National Flower
Vanda Miss Joaquim
2 petals, 3 sepals, 1 lip
(modified petal)
Orchid: 6 petals
Learn more about
Singapore National
Flower:
www.nparks.gov.sg/
plants/van/pla-vanvan.shtml
Orchid: 6 petals
NTU’s own flower:
Dendrobium Nanyang
Orchid: How many petals?
2 petals & 3 sepals?
Lip not obvious or
no lip (hybrid)
Flowers with 10 petals
Passion Flower
Probably 5 petals
& 5 sepals
Exception Type 3
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Mutations and hybrids that have been
created artificially also account for
exceptions
Marsh Marigold: 5 or 6 petals?
The 6-petal flower
is a mutant
4 or 5 petals?
Taken in Singapore
The 4-petal flower
is a mutant
Roses: How many petals?
Hybrids: many petals
Wild Roses: How many petals?
5 petals
Are you sure there is a pattern?
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Fibonacci: 1, 2, 3, 5, 8, 13, …
Lucas: 4, 7, 11 (we haven’t seen 11 petals)
Doubling (even nos.): 6, 10, 12, 14, 16, …
(we haven’t seen 12, 14, 16, … petals)
Petals: 1-8, 10-14 (cover most numbers!)
If can find 9 or 15 petals, this is rubbish!
So where is the Fibonacci pattern?
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The Fibonacci pattern comes mainly from
daisies: 13, 21, 34, 55 or 89
Botanists may disagree because some
‘petals’ are actually sepals or bracts
But we go by what we laymen see. Why?
So where is the Fibonacci pattern?
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E.g. if nature has fused
the 3 petals and the 3
sepals of the White Calla
Lily into 1 petal, why
call it 3 petals?
The Internet Search for 9 Petals…
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Marsh Marigold: “5-9
deep yellow petals”
But mostly 5 petals
6-petal is a mutant
“5-9 sepals; no petals”
Website can be wrong
The Internet Search for 9 Petals…
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Lesser Celandine: “5-9
yellow petals”
But mostly 8 petals
Website can be wrong
or the rest are mutants
The Internet Search for 9 Petals…
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Mayapple: “6-9 petals”
But mostly 6 petals
Website can be wrong
or the rest are mutants
The Internet Search for 9 Petals…
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Royal Ramparts: “9
deep red-purple petals”
Japanese Iris Nursery
Probably a hybrid
The Internet Search for 9 Petals…
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Áashild Kalleberg: “8-9 petals & 3 sepals”
Website says it is a hybrid
Some sites on dried flower arrangements
Conclusion: Flowers with 9 petals are
either mutants or hybrids
Websites are not always reliable
Websites on Fibonacci Numbers
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ccins.camosun.bc.ca/~jbritton/fibslide/jbfibslide.
htm (contains other patterns as well)
library.thinkquest.org/27890/applications5.html
How many ridges in a banana?
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Hint: It is a Fibonacci
number
ridge