Flora of Hawaii. Flora of Hawaii. Flora of Hawaii. Flora of Hawaii. native. or weeds

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1 since so isolated, it has a depauperate flora and consists entirely of waif elements derived from LDD individual islands tend to fit the expected number of species based on area - except most recent Hawaii native or weeds Argyroxiphium sandwicense - Haleakala silversword Passiflora mollissima - Banana poka endemism high in flowering plants 956 native species 89% endemic 216 native genera 15% endemic 87 native families 0% endemic 1,817 including introduced 69 including introduced 16 including introduced endemism highest in the world speciation far exceeds immigration Hawaiian flora so distinctive, often assigned its own floristic region Why so distinctive? Brighamia Lobeliaceae Brighamia Lobeliaceae

2 distance from source area and thus few immigrants archipelago effect and inter-island speciation extraordinary rich and diverse habitats available 38 community types recognized disharmonic flora only 3 native orchid species disharmonic flora only 1 native palm genus native gymnosperms and primitive angiosperms absent but many introduced orchids that become naturalized Dendrobium & honey bees Pritchardia beccariana

3 disharmonic flora - 15 largest families of native species large source area families under represented small Campanulaceae - lobeliads and bellflowers - over represented immigrants: 270 (or less!) gave rise to 956 native angiosperms 1/10 th of colonist generates 1/2 of species! Cyrtandra Cyanea Pelea immigrants: similar story with other biota one American finch gave rise to 33 extant and 1 extinct species of honeycreepers immigrants: similar story with other biota 800 land molluscs from 20 colonists 5,800 insects from 250 colonists

4 immigrants: but different story for ferns! LDD mechanisms 168 ferns from 135 colonists - implying constant immigration (lack of genetic isolation) and/or few speciation events 1% A air 39% BI internal 13% BM mud Leptocophylla BI vs. 10% 12% BV BB viscid barbs/hooks Argyroxiphium BB 1% DF drift 9% DR drift - rare Sadleria - 6 species Polypodium - 1 species Acacia - koa DR Viola BM floristic affinities floristic affinities Leptocophylla Epacridaceae despite proximity of Hawaii to N America, almost half of colonists are of Austral-asian origin Viola few from Arctic-Beringia Plantago - plantain

5 floristic affinities floristic affinities Viola Viola langsdorfii woody violets considered closely related to South American violets Argyroxiphium 18-22% from western North America all native Hawaiian violets are polyploid and derived from polyploid races of one Beringian tundra species - the Alaskan violet adaptive radiation of Hawaiian silverswords silversword alliance of 3 genera and 28 species trees, shrubs, subshrubs, rosette plants, cushion plants, vines adaptive radiation of Hawaiian silverswords B. Baldwin verified that the Hawaiian silversword radiation derived from California the closest species is now called Carlquistia muirii this origin occurred about 5 mya rapid radiation at base

6 inter-island biogeography [ island[ hopping ] inter-island biogeography [ island[ hopping ] most speciation events occur on individual islands few successful inter-island colonizations movement is from older to younger islands Argyroxiphium Spiders Spinning Southeast! Tetragnatha T. pilosa 5 1 T. kauaiensis T. perreirai 6 T. tantalus T. kamakou T. kamakou T. quasimodo T. waikamoi T. quasimodo T. quasimodo 1 1 T. polychromata T. quasimodo 3 T. restricta 6 T. macracantha T. restricta T. brevignatha N 1 T. brevignatha 3 T. stelarobusta T. pallescens Geranium cuneatum inter-island biogeography - not all the same story! Geranium colonized late E. Maui and radiated and migrated speciating most recently on Kauai with ecological correlations! Geranium (pandemic) OG arboreum E. Maui sub-alpine multiflorum E. Maui sub-alpine cuneatum Hawaii sub-alpine tridens E. Maui alpine hanaense E. Maui bog humile W. Maui bog kauaiense Kauai bog Geranium arboreum Geranium hanaense

7 extinction: on-going process on islands (as well as immigration) extinction: rogue gallery of exotics but due to humans... Passiflora mollissima - banana poka 107 of 956 angiosperm species 11% extinct 23 of 956 species 38% extinct or threatened extinction: rogue gallery of exotics Miconia introduced into Hawaii as ornamental Miconia calvescens green cancer

8 Why the Hawaiian lobeliads? Why the Hawaiian lobeliads? largest group: 6 genera, 115 species) 1/9th of native flora considered derived from 3-5 separate colonizations phenomenal variation in habitat, life form, flowers, and fruits appear to have co- evolved with the endemic Hawaiian honeycreepers Why the Hawaiian lobeliads? What are the Hawaiian lobeliads? appear to have co- evolved with the endemic Hawaiian honeycreepers honeycreepers represent a separate adaptive radiation Lobelia gloria-montis Lobelia telekii - Mt. Kenya

9 What are the Hawaiian lobeliads? What are the Hawaiian lobeliads? Delissia Brighamii What are the Hawaiian lobeliads? What are the Hawaiian lobeliads? Clermontia Trematolobelia

10 What are the Hawaiian lobeliads? The Hawaiian lobeliads represent a single lineage/colonization! Cyanea The Hawaiian lobeliads - more spectacular adaptive radiation Remarkable divergent and convergent character evolution - but fruit color is perfectly consistent with relationships

11 Two clock calibrations - using Asterid fossils or using Hawaiian Island ages - place the differentiation of Hawaiian lobeliads at 13-1 mya Two clock calibrations - using Asterid fossils or using Hawaiian Island ages - place the differentiation of Hawaiian lobeliads at 13-1 mya Original colonist arrived in LaPerouse/Gardner Pinnacles - large volcanic islands mya Two clock calibrations - using Asterid fossils or using Hawaiian Island ages - place the differentiation of Hawaiian lobeliads at 13-1 mya One of the oldest radiations of extant Hawaiian biota - honeycreeper pollinators would not arrive for another 7-9 my Original colonist arrived in LaPerouse/Gardner Pinnacles - large volcanic islands mya

12 But... a 2008 paper shows that the 5 recently extinct Hawaiian Honeyeaters thought to be recently derived from AustralAsian Honeyeaters are in fact 1-17 my old and derived from an American clade - waxwings, silky flycatchers, and palm chats Assume nothing in Hawaiian natural history Frank Howarth, 1992 Hawaiian lobeliads 13-1 mya Hawaiian Honeycreepers 7 mya