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Diversity and Evolution of Monocots

Diversity and Evolution of Monocots

4 main groups:

Diversity and Evolution • Acorales - sister to all monocots • Alismatids of Monocots – inc. Aroids - jack in the pulpit • Lilioids (lilies, orchids, yams) – non-monophyletic . . . palms, spiderworts, , and – petaloid • Commelinids . . . – – palms – – spiderwort – – – – – grasses & sedges

Commelinids Commelinids • largest group of monocots ranging from palms to grasses

• strongly monophyletic!

• bound ferulic acid in cell walls (fluoresce under UV with ammonium hydroxide added)

• this feature allowed placement of Dasypogonaceae

4 genera - W Commelinids * - palms • theme: reduction of , loss of • the order has one family - also nectar, loss of zoophily, evolution of called Palmae • 190 genera and 2400 of and shrubs • tropics, , deserts, grass Mediterranean biomes

pickeral weed

rapatead bromeliad

*Arecaceae - palms *Arecaceae - palms

Malaysia • greatest center of diversity in • Rattan palms - a group that honors the Wallace Malay archipelago, then Biogeographic Line Amazonia • Asian distribution with few species passing through Sulawesi • depauperate in , but or New Guinea diverse in Rattan palm & generic distributions

Madagascar *Arecaceae - palms *Arecaceae - palms Great morphological diversity: in stature Great morphological diversity: largest of seed

Syagrus - lilliput palm of Paraguay - Chilean wine palm maldivica - palm or double nut

This of 1 species endemic to the Seychelles has generated interest in having the largest seed, and in that the shape of the *Arecaceae - palms seed has suggested the devil's work or aphrodisiacal properties. Great morphological diversity: largest

What is unusual about how this species was first discovered? Raffia - rattan Lodoicea maldivica - Seychelles palm or double nut . . . and largest *Arecaceae - palms *Arecaceae - palms

Vegetative characteristics Vegetative characteristics

• “woody” stems via primary • palmate or pinnate compound, thickening meristem or diffuse sheathing, plicate or folded secondary growth • essentially hardened leaf bases • single apical meristem: succeptible to frost

Roystonia

*Arecaceae - palms *Arecaceae - palms

Floral characteristics Floral characteristics

• inflorescence surrounded by • unisexual or bisexual spathe - once allied with aroids CA 3 CO 3 A 3,6,∞ G 3 or (3) *Arecaceae - palms *Arecaceae - palms

Floral characteristics Betel palm Classification: 5 subfamilies

• a 1-seeded berry or drupe • Nypoideae and are first diverging

Cocos

Nypa fruticans radicalis salt marsh

*Arecaceae - palms *Arecaceae - palms

Important palms: food Important palms: food -

Cocos nucifera - coconut *Arecaceae - palms *Arecaceae - palms

Important palms: oil, wax Important palms: horticulture

Elaeis - oil palm

Chyrtostachys - - Royal Palm in sealing wax palm Santa Monica

*Arecaceae - palms Commelinids

Important palms: horticulture 4 main groups: Palm House at Kew Royal Botanic Garden - largest • Acorales - sister to all monocots glass house in the world • Alismatids with the largest glass house – inc. Aroids - jack in the pulpit • Lilioids (lilies, orchids, yams) plant - Chilean wine palm – non-monophyletic – petaloid • Commelinids – Arecales – palms – Commelinales – spiderwort – Zingiberales –banana – Poales – pineapple – grasses & sedges Commelinids Commelinales + Zingiberales • theme: reduction of flower, loss of nectar, loss of zoophily, evolution of • 2 closely related tropical orders bracts • primarily nectar bearing but with losses • bracted

grass

pickeral weed pickeral weed spiderwort nectar pollen only nectar + bracts rapatead bromeliad

Commelinaceae - spiderwort - spiderwort Family of small herbs with succulent stems, stems jointed; sheathing. Family does not produce Inflorescence often bracted nectar, but showy flowers for insect pollen gathering.

Rhoeo - Moses in a cradle

Commelina erecta - Erect dayflower

Tradescantia ohiensis - spiderwort ohiensis - spiderwort Commelinaceae - spiderwort Commelinaceae - spiderwort

Flowers actinomorphic or • species rich in pantropics, CA 3 CO 3 A 6 G (3) zygomorphic especially Africa • floral diversity is enormous communis - day flower

Tradescantia ohiensis - spiderwort

Pontederiaceae - pickerel weed - pickerel weed

Aquatic family of emergents or floaters. Pickerel weed has glossy heart-shaped leaves, Water hyacinth () from superficially like Sagittaria but without net venation. tropical America is invasive species in Flowers are in congested showy purple inflorescences. subtropical areas of the world.

Eichhornia crassipes Water hyacinth invading

Pontederia cordata - Pickerel weed Pontederiaceae - pickerel weed - kangaroo paw Flowers are showy, insect pollinated with nectar glands - previously placed in !

Anigozanthus - kangaroo paw

Small family with floral nectar, species radiations in Australia and cordata - Pickerel weed South Africa

Zingiberales Zingiberales

• strongly supported group of 8 tropical • strongly supported group of 8 tropical families families • rhizomatous monocots with showy, • rhizomatous monocots with showy, nectared, but highly bracted flowers nectared, but highly bracted flowers • 3 shared features: 1. Parallel-pinnate leaves, often • 3 shared features: 2. Bracted flowers distichous and inflorescences Zingiberales Zingiberales

• strongly supported group of 8 tropical • order fairly well known based on DNA and morphology families • show interesting trends in (1) fusion of perianth and (2) loss and staminode development • rhizomatous monocots with showy, floral pattern nectared, but highly bracted flowers P • 3 shared features: 3. Inferior ovary S A S A A A A P A P S 3 fused sepals 3 separate petals 5 fused sterile anthers (labellum) DNA-based Zingiberales “rhizogram” by John Kress 1 fertile anther

Poales I - showy flowers Poales I - showy flowers

4 main groups: • showy flowers, • Acorales - sister to all monocots insect or • Alismatids pollinated – inc. Aroids - jack in the pulpit • Lilioids (lilies, orchids, yams) – non-monophyletic • +/- reduced – petaloid flowers, insect or • Commelinids – Arecales – palms wind pollinated – Commelinales – spiderwort – Zingiberales –banana – Poales • reduced – pineapple flowers, wind – grasses & sedges pollinated * - pineapples *Bromeliaceae - pineapples • mainly epiphytic, but terrestrial as well in • key adaptations: CAM photosynthesis, modified inhospitable regions trichomes or scales, “tank” formation

Tank (water impounding)

Scales (water & nutrient uptake)

*Bromeliaceae - pineapples *Bromeliaceae - pineapples • key adaptations: CAM photosynthesis, modified • preadaptations to carnivory in and trichomes or scales, “tank” formation

• scales very visible in

Amino acids radioactively labeled being incorporated into usneoides in the scales of live oaks Brocchinia Brocchinia Catopsis *Bromeliaceae - pineapples *Bromeliaceae - pineapples • inflorescence heavily bracted and often the __ CA 3 CO 3 A 6 G (3) or G (3) attractant • petals showy, but not the sepals • 2 sets of 3 • superior or inferior ovary, with twisted styles • berry or capsule

*Bromeliaceae - pineapples *Bromeliaceae - pineapples • bromeliads are an American family: 2600 species, 56 • pineapple not native to Hawaii - along with two other genera ingredients of Hawaiian Punch

1 species of in west Africa - vicariance or dispersal?

guava passion fruit *Bromeliaceae - pineapples *Bromeliaceae - pineapples • classification traditionally had three subfamilies • tillandsioids

tillandsioids pitcairnioids bromelioids

Tillandsia usneoides and T. grandis

Vriesea Incan ceremonial dance

*Bromeliaceae - pineapples *Bromeliaceae - pineapples • bromelioids • pitcairnioids Brocchinia

Ananas - pineapple

Achmea *Bromeliaceae - pineapples *Bromeliaceae - pineapples

• 2 subfamilies natural Guayana Highlands of southern based on DNA and adjacent areas of and - the higher • pitcairnioids broadly elevation “tepuis” are rain paraphyletic drenched and extremely nutrient poor • Brocchinia sister to rest of family • origin of family in Guayana Shield of

*Bromeliaceae - pineapples *Bromeliaceae - pineapples

When did the When did the Atlantic disjunction Atlantic split occur? Atlantic disjunction occur? Bromeliaceae

Long distance dispersal to Africa! African species divergence is 15-13 mya

DNA calibrated Pitcairnia saxicola Picairnia feliciana in west Africa with monocot Costa Rica *Bromeliaceae - pineapples Rapateaceae - a tepui family • 16 genera and nearly 100 species from the Guayana Shield Where did the African species come from?

• African species originated from Andes!

Rapateaceae - a tepui family Rapateaceae - a tepui family • most species are pollinated by pollen-gathering bees • most species in the Guayana Shield but one in west Africa • hummingbird pollination has evolved once in a of two genera

Is the African Mascolocephalus a product of Atlantic vicariance with closest Guayana Shield relatives, or a product of long distance dispersal? Rapateaceae - a tepui family

Recent long distance dispersal to Africa! African species divergence is 8-6 my whereas Atlantic separation is 80+ mya

Atlantic split

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