16. Maori mystery

Question 1

When did the Earth’s landmasses begin to have good resemblance to today?

Answer 1

Cretaceous, more similar in the Paleocene (North America and Europe fully formed)

Question 2

What current continents was Gondwana composed of?

Answer 2

Mostly Southern ones
South America, Africa, Arabia, Madagascar, India, Australia, New Zealand and Antarctica

Question 3

What is Nothofagus?

Answer 3

A genus of trees and shrubs closely related to Oak and Beech

Question 4

Why are Nothofagus so easy to recognise in the fossil record?

Answer 4

They have quite large seeds and very distinctive pollen.

Question 5

Where is Nothofagus found?

Answer 5

Australia, New Zealand, Papa New Guinea, Indonesia, a few other oceanic islands (e.g. in the pacific ocean)

Question 6

What is vicariance?

Answer 6

When the geographical range of a biota is split into discontinuous parts by the formation of a physical or biotic barrier to gene flow/dispersal

Question 7

What is allopatric speciation?

Answer 7

When two or more closely related species are separated by reproductive isolation (usually by vicariance)

Question 8

State the two explanations for Nothofagus’ distribution.

Answer 8

1. Vicariance explanation
2. Dispersal explanation

Question 9

How does vicariance explain the modern distribution of Nothofagus?

Answer 9

Using previous continent arrangements of Gondwana which would’ve put New Guinea, New Zealand, Australia and South America all very close.

Question 10

What problem stops Vicariance from fully explaining the distribution of Nothofagus?

Answer 10

Nothofagus is found on some islands that were never connected to other land, e.g. islands in the Pacific Ocean

Question 11

What are some ways plants can be dispersed island to island?

Answer 11

Seeds carried on wind, birds carrying seeds, vegetation rafts.

Question 12

What recent discovery has been made about the continent New Zealand is on?

Answer 12

New evidence that New Zealand is part of a mostly submerged continent ‘Zealandia’

Question 13

What is so interesting about the uniqueness of New Zealand’s biota?

Answer 13

New Zealand has very very distinct biota from that of other connected continents from Gondwana

Question 14

What are the 3 categories of unique New Zealand species? (based on origin)

Answer 14

Relic, Novelty, Immigrant

Question 15

What is a relic species?

Answer 15

A species from before the continents split that has died off/evolved on other continents recently

Question 16

What is a novelty species?

Answer 16

A species that is new to Zealand and has evolved from a relic/immigrant species.

Question 17

What is an immigrant species?

Answer 17

One that has moved to New Zealand and may have evolved/died elsewhere

Question 18

What is the molecular clock model?

Answer 18

Studying mutation rates of biomolecules to work out when lifeforms diverge

Question 19

Are most of New Zealand’s species immigrants, novelty, or relic species?

Answer 19

Most of them are new arrivals (immigrant)/ evolved from recent arrivals.

Question 20

What is the ‘Oligocene drowning’?

Answer 20

A theory that New Zealand was almost entirely submerged during the Oligocene (34 - 23Ma)

Question 21

How might the ‘Oligocene drowning’ theory account for why New Zealand’s species are mostly new arrivals?

Answer 21

New Zealand being submerged would’ve killed off most of its endemic species - leaving it depauperate and prime for niches to be filled once it emerged again.

Question 22

Most of New Zealand’s species arrived in the last ____ million years.

Answer 22

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