Flowers with 1 petal very rare White Calla

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 o o 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 o 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 o 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? o o o 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? o o o 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? o 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… o o o 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… o o o 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… o o o Mayapple: “ 6 -9 petals” But mostly 6 petals Website can be wrong or the rest are mutants

The Internet Search for 9 Petals… o o o Royal Ramparts: “ 9 deep red-purple petals” Japanese Iris Nursery Probably a hybrid

The Internet Search for 9 Petals… o o o 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 o o ccins. camosun. bc. ca/~jbritton/fibslide/jbfibslide. htm (contains other patterns as well) library. thinkquest. org/27890/applications 5. html

How many ridges in a banana? o Hint: It is a Fibonacci number ridge