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  • We will examine adaptive radiationsin the context of the Hawaiian Islands

    Adaptive radiations

    Adaptive Radiations Hawaiian archipelago - the examplefor adaptive radiations

    Getting there is half the problem . . .but then they cant go homeagain

    Sherwin Carlquist, 1965

    Hawaiian archipelago - the examplefor adaptive radiations

    If one were to stand at the top of Mauna Loa, he could see all the climes of theworld at a single glance of the eye

    Mark Twain, 1866

    Hawaiian archipelago - the examplefor adaptive radiations

    Assume nothing in Hawaiian natural history

    Frank Howarth, 1992

  • Hawaiian archipelago - the examplefor adaptive radiations

    Most remote island system in the world settled in 1st millenium byPolynesians

    made known to science byCaptain Cook in 1778

    Hawaiian BiotaHawaiian biota: most are found nowhere else in the world and exhibit traitsuncharacteristic of their taxa

    around 1,000 species of flowering plants

    225 species of ferns and allies

    Hawaiian biota: most are found nowhere else in the world and exhibit traitsuncharacteristic of their taxa

    nearly 5,800 species of insects

    130 species of spiders

    Kamehameha butterflyHappyface spider

    Hawaiian BiotaHawaiian biota: most are found nowhere else in the world and exhibit traitsuncharacteristic of their taxa

    230 species of birds

    800 species of terrestrial molluscs

    Land snailsKauai Oo

    Hawaiian Biota

  • Hawaiian biota: most are found nowhere else in the world and exhibit traitsuncharacteristic of their taxa

    no amphibians

    no terrestrial mammals

    Hawaiian monk sealHawaiian bat

    Hawaiian BiotaHawaiian biota: extinction on-going process both in past and present

    Hawaiian honeycreepersExtinct snail, flightless duck, lobeliad

    Hawaiian Biota

    Hawaiian Archipelago

    132 islands, reefs, & shoals

    2,580 km on SE-NW line

    99% of land lies on 8 mainislands near the hot spotbelow Loihi

    Hawaiian Archipelago

    hot spot stationary relative toPacific Plate motion

    forms hot spot trace

    potassium-argon datingindicates oldest islands furthestfrom hot spot

    hot spot stationary relative toPacific Plate motion

  • Hawaiian Archipelago

    plate motion changed 43 mya

    oldest seamounts subductedinto Aleutian Trench

    plate motion changed 43 mya

    43mya

    Hawaiian Archipelago

    Islands (and shoals) are simplyemergent tops of great underwatervolcanoes

    up to 10km above ocean floor

    Mauna LoaUSGS GLORIA side sonar

    Hawaiian Archipelago

    actually double hot spot 30km apart

    Loihi to Mauna Loa

    Kilauea to Mauna Kea

    HawaiiOahu

    Hawaiian Archipelago

    progressively older ages of islands well known

  • Hawaiian Archipelago

    real estate signs on recent lavaflow (80 years) on Big Island

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    Kauai Present

    NihauKaula

    Oahu

    Maui

    Loihi Seamount

    Molokai

    LanaiKahoolawe Hawaii

    Hawaiian Archipelago

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    Kauai

    0.5 Million Years Ago

    Nihoa

    NihauKaula

    Oahu

    Maui

    Mahukona

    Hawaiian Archipelago

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    Kauai

    1 Million Years Ago

    Nihoa

    NihauKaula

    OahuMaui

    Hawaiian Archipelago

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    Kauai

    2.5 Million Years Ago

    Nihoa

    NihauKaula

    Oahu

    Hawaiian Archipelago

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    160 158 156 154

    Necker

    Kauai

    5 Million Years Ago

    Nihoa

    NihauKaula

    Hawaiian Archipelago

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    Gardner Pinnacles

    La Perouse PinnaclesNecker

    Nihoa

    7.5 Million Years Ago

    Hawaiian Archipelago

    Hilo (windward and wet) vs. Kona Coast in Hawaii (leeward and dry)

    Hawaiian Climate primary weather pattern is northeasterly trade winds severe kona winds come from leeward side

  • Hawaiian Climaterainfall patterns

    tall mountains have dry summit (eastMaui)

    shorter mountains have extremely wetsummits (Kauai)

    steep, windward mountains (Oahu) havewet summit but drier Pali cliffs

    Hawaiian Climaterainfall patterns

    double mountain system (as in Oahu)sets up complex rainfall gradient and adiversity of ecosystems

    Hawaiian Climaterainfall patterns

    Waialeale on oldest (most eroded)island of Kauai is wettest spot in Hawaiiand possibly in the world

    11.5 m of rain and presence of theAlakai Swamp

    Hawaiian Climaterainfall patterns

    Puukukui (5788 ft) on west Maui is 2ndwettest spot; xeric summit of Haleakala oneast Maui is 10,023 ft

    Greensword bog - west Maui

  • Hawaiian Climaterainfall and porous soils

    fewer waterfalls (permanent)

    Greensword bog

    fewer bogs than expected

    more pronounced deserts