Lecture 1

Question 1

what is the tropics?

Answer 1

an area between the tropic of cancer (23.4 degrees north) and the tropic of capricorn (23.4 degrees south)

Question 2

what can the tropics also be know as?

Answer 2

equitorial zone

Question 3

what is a temperate climate like?

Answer 3

follows a cycle and is very varied

Question 4

what is a tropical climate like?

Answer 4

more rain, higher temps, less cycle (stable temps)

Question 5

how much rainfall does a rainforest have per year?

Answer 5

over 2m

Question 6

what does a hot and wet climate result in?

Answer 6

wetter and drier seasons

Question 7

describe the structure a tropical forest?

Answer 7

tall
dense
dark under canopy (reached by 1-2% sunlight)

Question 8

there are lots of different types of tropical forests what are 4 big differences?

Answer 8

1) continental variation e.g. the amazon, the congo
2) hydrology e.g. within the amazon there is areas of dry (terra firme) and flooding (varzea)
3) altitude e.g. Andes subtropical cloud forest
4) rainfall e.g. can get dry forests (Tumbesian dry forest)

Question 9

why are tropical forests important ? (5 points)

Answer 9

1) most species on Earth
2) enigmatic wildlife (difficult to understand)
3) most endemic species
4) highest densities of species on Earth (hyperdiversity)
5) typified by complex networks of interactions

Question 10

describe hyperdiversity in the tropics?

Answer 10

1 hectare can have 650 tree species - massive number of species per area

Question 11

5 examples of network interactions within tropical forests

Answer 11

1) predation (large predators exert top down effects on smaller predators
2) nutrient cycling
3) plant pollination by insects, birds and bats
4) seed dispersal by birds and mammals
5) symbiotic relationships where species live together and trade benefits

Question 12

why do tropical forests matter?

Answer 12

they provide key ecosystem services ‘the provision of a natural resource or process that is valued by humankind’

Question 13

examples of key ecosystem services

Answer 13

carbon storage, wood fruits and animal protein, hydrological services ( rainfall and temp control, erosion and flood protection)

Question 14

what is the global biodiversity crisis?

Answer 14

man is causing the 6th mass extinction - biodivrsity loss is most severe in rainforests

Question 15

what activities are causing most species loss?

Answer 15

habitat loss and degradation and overexploitation

e.g. farming and fragmentation, logging and hunting

Question 16

what are devils gardens?

Answer 16

a large stand of trees dominated by one or two ant plant species

Question 17

whats the relationship between ants and ant plants?

Answer 17

Duroia hirusta plants provide M. Shumanni ants with housing in domatia - can be very large with millions of ants - colonies can survive for 800 years

Question 18

what are domatia?

Answer 18

structures produced by plants for ants to use - small chambers in the plant that provide shelter - intended for symbiotic relationships

Question 19

what is the local legend to explain devils gardens

Answer 19

known as spirit clearings - invisible villages of spirits- swollen trunks caused by fires set

Question 20

what is the actual cause of swollen trunks in devils gardens?

Answer 20

inhabited by the workers, brood and queens

Question 21

what is the benefit gained for the trees

Answer 21

the workers kill other understorey plants by injecting them with formic acid - creates clearing for host plant to survive