Galapagos

When did Charles Darwin reach the Galapagos Islands (exact date)?

Sept. 15th, 1835

What is the name of the person who allegedlyh "discovered" the Galapagos Islands?

Tomas de Berlanga (March 10th, 1535)

How did Berlanga find the islands?

he floated (boat with no wind - ship was becalmed) for a long time

Why was Floreana used frequntly by pirates and whalers?

It was the only water found by the spanish at the time with a freshwater source.

What type of bird species did Darwin first collect that led to his speciation hypothesis?

mockingbird (3 different species)

Wha other animal was important in Darwin's speciation hunch and why?

Galapagos Giant tortoise; he heard from others that toirtoises on different islands had different characteristics.

true/false: Darwin knew that the Galapagos finches he collected were of the finch species

false; he thought the finches belonged to many groups

What is one piece of evidence (relating to mammals) that an island was created in the middle of the ocean by volcanic activity as opposed to being a fragment that was broken off of existing land?

absence of warm-blooded terrestrial animals

What tectonic plate are the galapagos found on?

the Nazca plate

What three plates compose the galapagos hotspot?

the pacific plate, the cocos plate, and the nazca plate

The Galapagos plume model shows a hotspot under which island(s)?

Fernandina and Isabela

Why do volcanoes subside?

• erosion

  flexure of oceanic lithosphere due to weight of magma

• Thermal contraction of

flexure of oceanic lithosphere due to weight of magma

thermal contraction of oceanic lithosphere

What significant event happened in 1959? How about 1998?

1959: the Galapagos is named a National Park

1998: The Galapagos is named a marine reserve

Name the 13 main Islands found in the Galapagos

Pinta, Marchena, Santiago, Santa Cruz, Floreana, Española, San Cristóbal, Fernandina, Isabela

Which islands are inhabited?

San Cristóbal, Santa Cruz, Isabela, Floreana

True/false: due to rising sea levels and the fact that the lat glacial maximum was more than 20,000 years ago, the islands are bigger in size than they have been in the past

FALSE; they are smaller

Explain the underlying process that encompasses the theory of island biogeography

the effect of island area and isolation on species richness is mediated by immigration and extinction

name the currents that impact the seasonality of the galapagos, their temperature (hot or cold) and which direction they flow (towards or away from the mainland)

Peru coastal currents (Peru and humboldt) - cold water, away from mainland (NW)

South Equatorial current -warm, away from mainland

Panama current (Niño flow) - warm, away from mainland

Cromwell current - Cold, towards mainland

What are the major effects of the three main currents that impact the galapagos?

• air temp is cool (washed by cold water)

• few tropical storms

• net flow from S. America towards the west

True/false: on islands, you are likely to find more reptiles than amphibians, birds than mammals, and light plant seeds than heavy plant seeds

true

explain the two types of speciation and how they differ.

dispaersal: movement of individuals creates two separate species

vicariance: presence of a physical barrier creates two separate species

List some ecological responses to empty niche space

loss of unnecessary traits and changes to take advantage of empty niches

what phenomenon was experienced by finches when they arrived to the galapagos millions of years ago? What other animal experienced this?

adaptive radiation; land snails

Land snails experienced mostly ___________ speciation

allopatric

describe the history of galapagos tortoise population fluctuation on the islands

Towards the end of the 18th century, whalers and Buccaneers overharvested tortoises for meat and also introduced domesticated animals that ruined tortoise habitat and vegetation

tortoise populations severely declined in population and some were exirpated

A captive breeding program started in 1965 that successfully reintroduced the Española tortoise

There have also been successes in Santa Fe and Pinta

explain the behavioral changes experienced by the flightless cormorant due to lack of predation and abundance of food.

flightlessness, being extremely sedentary, very large, low vagility

What is the isalnd rule (hint: size shifts)

Species get smaller or bigger depending on the

resources available in the environment.

Pattern: size increase of small vertebrates and

size decrease in large vertebrates.

When does the garúa cloud band form?

inermediate islands and high islands (but doesn't cover everything on high islands)

marine iguanas have both _________ and ___________ island genetic variation.

among, within

Pieter taught us an interesting fact about the Gakapagos Hawk; what was that fact and how does it relate to strange behavioral changes experienced by island species?

they form "harems" (not really)/participate in cooperative polyandry (1 female and 2-8 unrelated males); paternity randomly distributed

What are the two kinds of lava found on the islands and how do they differ?

A'a lava: Has a jagged surface, thick flow, and cools quickly

Pahoehoe lava: has a smooth surface, thin flow, moves slowly and cools slowly

What is the function of upwelling?

to bring nutrient-rich water from the depths of the ocean to the surface

During the warm season, winds come from the ___________-, and during the dry season, winds come from the __________

east, southeast

true/false: there are choppier seas during the warm/wet season than during the dru season.

FALSE (choppier seas during the dry season)

What is the primary function of mangroves?

connection w/ coral reefs via mycorrhizal fungi

Overall features of the Islands:

1. _____ species diversity

2. ____________ disharmony

3. _________ (large/small) populations

4. High __________

5. _______ species vulnerability

1. low

2. taxonomic

3. small

4. endemism

5. high

What were the 2 main reasons that many organisms were unable to colonize upon arriving on the islands?

1. inhospitable conditions

2. lack of reproductive viability

explain Equilibrium Theory

colonization less likely the more remote from mainland and depends on number of existing species present (more species = less likely new arrival will colonize). Also, extinction rate decreases with size of island

Are there more or less species found on the islands when compared to Ecuador?

less

Name the seven endemic genera of plants found on the islands

• darwiniothamnus

• leocarpus

• Macraea

• Scalesia

• Brachycereus

_jasminocereus

-Sicyocaulis (now extinct)

name this plant genus

opuntia

name this plant genus

scalesia

name this plant genus

brachycereus

Name three common features of evolution in isolation (hint: one only applies to birds) and list examples of each

gigantism (giant tortoises), fearlessness (red footed booby), flightlessness (flightless cormorant)

Name two species that are examples of restricted distribution in the Galapagos

geckos (limited to S. Cristobal, Santa Fe, and Wolf island)

rice rats (Santa Fe, Fernandina, Santiago)

iguanas

finches

What subject did Darwin first enroll in, and why did he quit?

Medicine; he quit because blood made him queasy

What second degree did Darwin pursue?

Theology

After studying Theology, what did Darwin become?

An entomologist

What three main concepts was Darwin looking to understand when he first visited the Galapagos?

• the unity of life

• the diversity of life

• how organisms relate to their environment

What are these three main concepts a result of?

Descent with modification through natural selection

"The ____________ Mockingbird is the most widespread of the four species, occurring on all

major islands apart from Española, San Cristóbal and Floreana. It includes several

subspecies, among them the smallest mockingbird in the archipelago. Like all Galapagos