Biodiversity

Question 1

What is LUCA?

Answer 1

It stands for ‘last universal common ancestor’. So, all life on Earth is related to LUCA.

Question 2

What is a species?

Answer 2

A species is difficult to define. It implies a genetically closed population, so that organisms from the same species can cross-fertilise. Often it is based on gross morphology.

Question 3

How can we tell when isolated populations of a species separated?

Answer 3

DNA can be used to tell when this happened. However, whether humans choose to call them a different species is a human choice.

Question 4

How much variation can you have in a species before you class it as two different species? (According to the rule of thumb, s10)

Answer 4

You can have 1-2% variation within a species, while greater than 10% is 2 species. 8% is the new 0.05

Question 5

What is an endemic species?

Answer 5

A species confined to a small geographical area.

Question 6

Name one bird species endemic to the UK. Where does it live?

Answer 6

the Scottish crossbill /Loxia scotica/. It only lives in the Caledonian pine forests in central Scotland.

Question 7

Name a subspecies of bird that is endemic to the UK.

Answer 7

The red grouse Lagopus lagopus scoticus is endemic to the British Isles, but is a subspecies of the mainland willow grouse.

Question 8

Name an endemic species of UK plant,

Answer 8

The Scottish primrose Primula scotica is confined to the north coast of scotland, where it may be locally common.

Question 9

Give an example of a species that was a new species but was proved (via DNA) that it was not.

Answer 9

A new orchid Young’s Helleborine /Epipactis youngii / appeared in Northumberland in the 1980s. Then the DNA people had a look and proved it wasn’t new.

Question 10

What is meant by ‘conservation’?

Answer 10

it means preserving the existence of life-forms.

Question 11

‘Animals are best left in the wild’, true or false?

Answer 11

False. The Arabian Oryx was saved as a species by capturing the whole wild population. Global extinction is a worse outcome than having the species confined to zoos.

Question 12

What is the deontological principle in regards to animals in cages?

Answer 12

Animals must not be kept in cages. However, in 2010, animal liberations released 5000 mink from a farm in Donegal. Most were captured but 100 got away and caused great ecological damage (by preying heavily on other species.

Question 13

Name a species that is known to be morphologically unchanged for over 400 MY.

Answer 13

The inarticulate brachiopod (lampshell) /Lingula/

Question 14

Why is it so difficult to prove extinction of some species?

Answer 14

They can be difficult to find. It would be unlikely that a mammoth would go undiscovered but failure to find a small beetle doesn’t necessarily mean it is extinct.

Question 15

How often do species go extinct?

Answer 15

According to the fossil record, one species goes extinct per million years. Though there are a few points in the geological record where extinction rates increase hugely, marking the end of one geological period and the start of another. These are Mass Extinction Events.

Question 16

Define mass extinction event. (MEE)

Answer 16

is a widespread and rapid decrease in the biodiversity on Earth.

(Try and get a citation)

Question 17

What was the most recent MEE? What was unusual about it?

Answer 17

The most recent mass extinction started c. 10,000 BP – the Pleistocene extinction event.

all other MEEs removed small animals as well as large –the Pleistocene event was a selective removal of large species.

Question 18

What caused the Pleistocene MEE?

Answer 18

Most likely it was our ancestors, hence why it was only large species that went extinct.

Question 19

What is biodiversity as defined by the U.N. Convention on Biological Diversity (1992)?

Answer 19

‘the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems’.

Question 20

What is a key point in the conservation conservation management of a species?

Answer 20

Often a key point in conservation management is to maintain the diversity of habitats: this maximises the diversity of species.

Question 21

What is the clearest pattern in biodiversity?

Answer 21

The clearest pattern is with respect to size. There are many more species of small organisms than of large ones. Roughly 10* smaller = 10* more species.

Question 22

Which species is the most species-rich group on Earth?

Answer 22

Beetles are the most species-rich group on the planet (though bacteria could probably beat them if we could only isolate them all).

Question 23

Name a pattern in the distribution of life.

Answer 23

a pole-tropical gradient. there are vastly more species of almost everything in tropical areas than cooler ones. (Mayflies and salamanders don’t follow this rule). No-one knows why this is (though people do speculate).

Question 24

What are centinel species and who coined the term?

Answer 24

It is the name for species that we do not know about but are probably losing (e.g. due to tropical forest destruction). EO Wilson coined the term.

Question 25

If 2 different looking groups of animals interbreed, are they the same species?

Answer 25

Yes, if they share the same DNA barcodes (e.g 28S RNA; mt Cytochrome oxidase 1).