nz biodiversity Flashcards
(199 cards)
more h——geneity means greater diveristy
heterogeneity
what percentage of plants are endemic in NZ
80%
why are mosses and ferns less endemic than grasses
mosses and ferns are much older groups
and they use spores
grasses 84% endemic
mosses 21% endemic
give some examples or missing plants in nz
cycads
horsetails
pine trees - introduced through forestry
give some animal groups that are missing in nz
snakes
turtles
maruspials
scorpians
describe the effect the break up of gondwana had on NZ
origin of zealandia - isolation of ancestral NZ landmass
- genetic isolation from australia populations become widely different over time
isolated from speceis radiations elsewhere
describe the oligocene drowning of nz
the continent of new zealand is largelry submerged in the oligocene
- coastal thining
give evidence for the oligocene drowning
marine fossils present on land
marine rocks found inland
give some evidence to suggest that the oligocene drowning wasnt that server
pollen grains found in pores in the ground - land plants must have been continuously living there
fossil record shows moa and tuatara
what effect did the oligocene drowning have on nz biota
sinking would have lead to reduced surface area and hence greater competition - island biogeogrpahy
smaller island has a reduced carrying capacity
what are the two ´types´os island new zealand could be
fragment island
darwinian island
desccribe the evidecne for nz being a fragment island what would this mean
ancient flora and fauna from gondwanan origin
ancient microcosm or moa ark
some plants and animals are most cloesly releated to gondwana species
e.g. beech in southern alps relatred to south america and pacific islands
a vicarainace hypothesis - barrier to gene flow
describe the evidence for nz being a darwininna island
phylogenetic studies and molecular clock find some groups arent that old
has never been connected to another island
everyhting must have arrived by dispersal
disperal is a rare event but over a large amount of time it is possible
would suggest largely submerged by the drowning
how do we have old lineages on nz if it was a fully submerged darwinian island
close relatives on fragments of gondwana dispersed back after the drowning
a fragment island suggest what about the oligocene drowning
it didnt happen
old lineages came from zealandia before it split offf then remained here ever since
a —– lineage can disconut vicariance but an —– lineage doesnt discount dispersal
young ç
old
new zeland is both a fragment and a darwinian island
some examples to young to be explained by gondwanan origin
after the oligocene drowning what was the next thing to happen in nz
miocene tectonic activity
which two plates does nz sit on
pacific and austrlian plate
volcanoes produce a ——– island
darwinian
describe how miocene tectonci activity could have saved organisms from the oligocene drowing
huge amount of tectonic uplift
- making mountins which without erosin could have been 16 to 18 km high
give general effects the miocene activity had on biodiveristy
creates an alpine climate and niches
soil is uplifted and brings nutreints avlaible
vicariance - isolates species
volcanoes produce new freshwater environments - e.g. lake taupo
also produce fertile soil but also could kill predators
increase heterogeneity which increase diveristy
give examples of speies that would not exist without the uplift caused by miocene tectonic activity
mount cook lilly and the kea
give examples of alpine habitats
alpine lakes
scree
tundra
snow covered