Human Bio Unit 2 - Domesticating Animals and Plants

Question 0

What was the most important plant food grown by early farmers and why?

Answer 0

Cereal grasses

Rich in starch

Can be stored when dry

Question 1

How do humans change the characteristics of animals and plants?

Answer 1

Selective breeding

Question 2

How were cereal plants accidentally selectively bred?

Answer 2

Farmers went to save seeds

Any grains attached to a fragile rachis would fall to the ground and not be collected

They could only collect the ones on strong rachis

Question 3

What is a rachis?

Answer 3

Central stem of a cereal crop

Question 4

What happened when early farmers realised some plants produced bigger and better grains than others?

Answer 4

They chose the best as seed for the next year

Ate the not so good grains

Question 5

What was the first domesticated wheat and when was it grown?

Answer 5

Einkorn - Triticum monococcum

9000 years ago

Question 6

What was the problems with einkorn?

Answer 6

Didn’t produce a high yield

Question 7

Emmer wheat

Answer 7

Triticum dicoccom

Early wheat

Accidental hybrid of einkorn

Grow in parts of Israel

Question 8

The hybrid wheat formed by emmer and a wild grass and when it was?

Answer 8

About 7500 years ago

Common wheat

Triticum aestivum

Question 9

Where was the wheat used in civilisations of Mesopotamia and Ancient Egypt?

Answer 9

Common wheat

Question 10

What was the type of wheat humans selectively bred in the past and why?

Answer 10

Tall, strong stemmed wheat

Easier to harvest with a sickle

Less likely to lodged

Question 11

Lodging

Answer 11

When crops were blown over by wind and rained

Meant the crop was usually spoiled

Question 12

How has wheat changed in the past 60 years?

Answer 12

Higher yielding

Shorter stems

Question 13

What has caused crops to be grown with shorter stems in recent years?

Answer 13

Machinery like combine harvesters can easily harvest crops, even if they have short stems

Question 14

Advantages of short stemmed crops?

Answer 14

Less prone to lodging than tall stemmed crops

More energy from sunlight can go towards growth of the grain rather than growth of the stem

Question 15

What has modern cattle (Bos tauros) been bred from originally?

Answer 15

Wild aurochs

Bos primigenius

Question 16

Aurochs

Answer 16

Original cattle

Fierce and strong

Long horns

Wouldn’t have been easy to domesticate

Question 17

When were the aurochs first domesticated?

Answer 17

About 8500 years ago

Question 18

Why did early farmers chose to domesticate ruminants like cattle?

Answer 18

Digested the cellulose they ate in grass, which can’t be used by humans directly, so they weren’t competing with humans for the same food sources

Have a natural herding instinct which made them easier to manage

Question 19

Define ruminants

Answer 19

An animal that digests plant based food

Question 20

What characteristics were early cattle selectively bred for and why?

Answer 20

Shorter horns, small size and more docile temperament so they were easier to control

Question 21

What were early cattle useful for?

Answer 21

Meat

Milk

Horn used for tools

Hide used to make clothing

Used to pull things like primitive ploughs

Question 22

How many different breeds of cattle as there today?

Answer 22

About 270

Question 23

What are the 2 categories cattle can be divided into?

Answer 23

Dairy cattle

Beef cattle

Question 24

Dairy cattle

Answer 24

Bred to produce milk

Lean

Strong feet so they could walk to the parlour and back regularly

Large udders

Capable of breeding regularly

Can produce high quantities of milk, or higher fat content milk

Question 25

Beef cattle

Answer 25

Bred for meat

Lots of muscle tissue

Strong bones

Large frames

Important that they are able to convert the food they eat into muscle efficiently

Question 26

Examples of dairy cow

Answer 26

Holstein-Friesians - high milk quantity

Friesians

Jersey - high fat content milk

Question 27

Examples of beef cattle

Answer 27

Herefords

Aberdeen Angus

Charolais

Question 28

When do we know humans definitely domesticated dogs?

Answer 28

14000 years ago

May have been earlier

Question 29

How did the dog most likely become domesticated?

Answer 29

Likely they hung around settlements for scrap food

Question 30

What were dogs domesticated from?

Answer 30

The wolf Canis lupus

Question 31

Ways early dogs were selectively bred

Answer 31

Fierce dogs were chased away and friendlier ones tolerated

Chose ones that barked a lot as it frightened off predators

Chose those with characteristics that made them look friendlier

Question 32

Roles of early dogs

Answer 32

Watchdogs

Scare off predators

Retrieved and carried carcasses when hunting

Follow animal scents

Question 33

What has happened with the breeding of the modern dog?

Answer 33

The dog has either been bred to be a working dog, hunting or rounding up cattle, or a companion to humans

Question 34

How does the domestication of cattle reduce biodiversity?

Answer 34

Kills competitors

Remove forests for grazing

Question 35

Describe how selective breeding could have been used to produce cattle with large muscles

Answer 35

Breed animals that show the desired characteristics

Breed offspring with chosen characteristics

Keep going until only the wanted alleles remain