Transcript Biomes: Islands & Evolution

Biomes: Islands &
Evolution
THE GALAPAGOS
ARCHIPELAGO
A Collaborative Project
TABLE OF CONTENTS
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Introduction
Island Geography & Life Forms
How & When Islands Formed
Endemic Species:
Galapagos Penguin
Galapagos Giant Tortoise
Introduction
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The Galapagos Islands is an
“Archipelago”
1574: Named “Galapago” meaning
“Saddle” for Giant Tortoise shell
1500-1700: Famous Hideout for
Pirates
1811-1844 Whaling Ships
1835: Darwin’s Visit which led to his
theory of evolution
Geography & Life Forms
Basic Geography Facts:
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Archipelago of Volcanic
Islands
Located around the
Equator in the Pacific
Ocean
600 miles West of
Ecuador
3,042 sq. miles of land
13 Main Islands, 5
Minor & 107 “Rocks”
& Inlets
Noteworthy Native Animal Species
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Galapagos Tortoise
Land & Marine Iguanas
Flightless Cormorant
Blue-footed Booby
Waved Albatross
Galapagos Penguin
Galapagos Hawk
Galapagos Sea Lion
Beginnings of Endemic Life Forms
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SEEDS: by wind and water
drop in rock crevices and
germinate by humidity
MARINE LIFE: strong and
cold ocean currents bring
sea lions, penguins
SEA BIRDS: fly to island
TORTOISES & IGUANAS:
float on vegetation or tree
trunks propelled by currents
Wind & Ocean Currents
Germinate Seeds
Marine Life
Reptiles
Weather
Humboldt Current brings cold water to the Galapagos
Many Microclimates; higher altitude… cooler & rainier
Two Seasons:
“Garua” (June-Nov): 72 degrees w/ cold winds, dense fogs, and
drizzles (called Garuas in Spanish)
Warm Season (Dec-May) 77 degrees w/ sun and occasional heavy
rains
How & When the Galapagos
Formed…
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5 Million years ago the
first Islands emerged
from the ocean floor
Layer upon layer of lava
spilled from underwater
volcanoes
As this volcanic activity
continues, new islands
are formed
The Galapagos are among the most
active volcanoes in the world…
This is La Cumbre volcano on Fernandina Island, April ‘09
The Archipelago of Volcanic Islands
is located atop the Galapagos
“Hotspot”
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A “Hotspot” is a place where Earth’s crust is being
melted from below by a Mantle Plume, creating
volcanoes
A Mantle Plume works like a lava lamp
The “Hotspot” is 20 million years old
Located in the East Pacific Ocean
Responsible for the creation of Galapagos Islands
2 Tectonic Plates move over the “hotspot”
4 major lava reservoirs feed the “hotspot”
The Galapagos Islands were formed by lava flows from the
“Hotspot”…….The Islands on the East side (closer to
“hotspot”) are older, while the islands toward the West are
younger.
Rare species of plants & animals
found nowhere else on earth inhabit
the Galapagos Islands
The Giant Tortoise
The Giant Tortoise Inspired Charles
Darwin….
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First Tortoises floated to the Galapagos Islands on
logs or vegetation
Evolved over millions of years into 15 distinct
subspecies living on different islands
Each island has Giant Tortoises with different shaped
shells
Numbers decreased due to Whalers & Turtle hunters
To avoid extinction, biologists have placed many in
captivity to facilitate breeding
Giant Tortoise facts:
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Belongs to species “Geochelone Elephantopus:
Mature at age 20-25 years
Grow up to 5 feet & weigh more than 500lbs
Lay only 2-16 eggs at a time
Eggs are buried for 4-8 months
Adaptation Strategies of the Giant
Tortoise
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Evolved into different subspecies to adapt to
each island’s specific microclimate and
vegetation
As vegetarians, the Giant Tortoise has a varied
diet of prickly pear cactus, fruit, bromeliads,
water ferns, leaves & grasses
Has a well developed sense of smell
Has a huge water storage capacity…can
survive more than 1 year without food or water
The Galapagos Penguin
The Penguins come to the
Galapagos….
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The cold Humboldt Current brought the
Penguins to the Galapagos from Antarctica
The Penguins depend on this cold, nutrient rich
ocean current
Congregate along rocky lava shores of
Isabela, Fernandina, Santiago & Bartolome
Islands…which are cooled by both the
Humboldt and Cromwell currents
Galapagos Penguin facts:
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Galapagos Penguins are the
smallest Penguins in the world
Penguins grow to be 20 inches tall,
weigh 5 lbs
Females are smaller
Cool off in cold water, swimming
slowly & gracefully
When searching for food, dive &
swim fast using flippers
Chicks stay w/ parents for 60 days
Threats …
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1987 El Nino Current: This current killed off
most of the small shore fish such as sardines
As a result, 75% of the Penguins died due to
lack of food
Less than 1,000 pairs remain
Now considered an endangered species
…..and Predators
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Snakes
Galapagos Hawk
Galapagos Sea Lion
Galapagos Sharks
Galapagos Crabs
The End
Sources Cited
Galapagos Conservation Trust: land animals of Galapagos, Jan. 2010.
www.gct.org/landfact.html
Global Volcanism Program. “Fernandina”
www.volcano.si.edu/world/volcano.cfm?num
La Cumbre Volcano. Galapagos Islands, April 16, 2009
http://geology.com/news/2009/la-cumbre-volcano-galapagos-islands.shtml
Vnir, Aster. “Volcanic Islands in the Pacific Ocean, 2005.
www.ersdac.or.jp/todaydata/032
White, W.M. “A Brief Introduction to the Geology of the Galapagos”, 1997.
www.geo.cornell.edu/geology/galapagoswww
WikiPedia, “Galapagos Islands”
en.wikipedia.org/wiki/galapagos_islands
WWF The Galapagos Species.
www.worldwildlife.org/what/wherewework/galpagos/species.html