TheTimes8April2020

32 2GM Wednesday April 8 2020 | the times

Wo r l d

to a mix of species that are tougher.”

However, he said that the species of

branching coral that had not recovered

well after previous bleaching provided

an important habitat for many fish

species. “Branching corals make all of

the nooks and crannies that the rest of

the biodiversity — the fish and so on —

depend on,” he said.

“So having fewer and fewer corals is

having a much broader effect, not just

on the corals themselves but in the

broader ecosystem.” Most damaging

for any coral, he said, was repeated

bleaching events in quick succession.

The Great Barrier Reef has experi-

enced five mass bleaching events, in

1998, 2002, 2016, 2017 and this year, all

caused by rising ocean temperatures,

which in turn were propelled by global

warming.

Park ranger

‘in dream

job’ is killed

by shark

Bernard Lagan

A young wildlife ranger following his

dream career was killed in a shark

attack on the Great Barrier Reef as he

cooled down after a day’s work.

Zach Robba, 23, an officer with the

Queensland parks and wildlife service,

was attacked by a large shark while

swimming with colleagues. He suffered

severe injuries to his leg, hand and

elbow. A doctor was rushed by helicop-

ter to the scene near North West Island,

about 370 miles northeast of Brisbane.

Mr Robba was winched up from the

rangers’ boat and flown to hospital but

died from his injuries on Monday night.

The attack was the third near North

West Island in just over three months

and continues a spate of shark attacks

across the Great Barrier Reef.

Police said that Mr Robba was swim-

ming with colleagues after they had

completed the day’s maintenance tasks.

As they swam back to their vessel Mr

Robba, who was at the rear of the group,

was attacked.

His mother, Sheree, and younger

brother, Max, told Brisbane’s Courier-

Mail that Mr Robba was “overjoyed”

with his recent posting to the town of

Gladstone as a wildlife officer.

“He was always willing to help people

out and go through life behind the

scenes without any notice,” Max said.

“He always loved parks and wildlife

since he was little, so when he found out

he was coming up to Gladstone to go

out to the reef he was overjoyed.

“He passed away doing what he loved

doing — swimming in the ocean and

working for Parks and Wildlife.”

The shark is suspected to have been a

tiger shark which can grow to 16ft and

has a reputation for eating almost any-

thing. It is common to the area.

In January a nine-year-old girl suf-

fered a bite wound to the back of her leg

and puncture wounds to her foot. A

lemon shark was suspected of that

attack. In late December a shovelnose

shark bit a man in shallow waters at

North West Island. He suffered minor

injuries to his right hand and leg. Last

October, two British backpackers were

attacked while snorkelling at Hook in

the Whitsunday Islands. One lost a

foot. A year ago a 25-year-old man suf-

fered serious thigh injuries when he

was attacked at Hardy Reef, also in the

Whitsunday Islands chain.

Those attacks followed another

fatality in November 2018, when Dan-

iel Christidis, 33, a doctor, was killed at

Cid Harbour at Whitsunday Island.

The origins of agriculture in western

Europe can be traced to two waves of mi-

gration from modern-day Turkey and

Ukraine that began about 8,500 years

ago, researchers in Sweden have said.

Farmers from Anatolia, that area of

Turkey west of a line drawn from the

southeastern shores of the Black Sea to

the Mediterranean, were the first to

move northwest, according to the team

at the University of Uppsala, who used

ancient DNA and carbon-dated plant

remains to show how plant cultivation

was introduced to areas then still

inhabited by hunter-gatherer societies.

That led to the Neolithic revolution,

nomads, in hierarchical chiefdom soci-

eties, and are thought to have been tall

and light-skinned, with brown eyes and

hair.

Their path across Europe is believed

to have been violent, since in many

places, including Britain, the existing

The Great Barrier Reef is suffering the

biggest mass coral bleaching on record,

with all three sections of its 1,500-mile

length affected, scientists said.

“We were really shocked. No scientist

expected to see three severe bleaching

events in just five years,” Terry Hughes,

head of the ARC Centre of Excellence

in Coral Reef Studies, said.

The findings confirm the worst fears

of marine biologists who delivered pre-

liminary findings last month and have

since completed a full survey of the reef.

Bleaching occurs when overheated

corals expel algae known as zooxan-

thellae, which provide much of their

energy and vibrant colour. Bleached

corals turn white and may die.

More than 1,500 species of fish, about

10 per cent of the world’s total, inhabit

the reef and many rely on the corals.

The reef, which is made up of 2,900

separate reefs and 900 islands, spans

133,000 square miles off Queensland,

an area almost the size of Germany.

High temperatures and bush fires in

February contributed to the warmest

water around the reef since records

began in 1900.

Professor Hughes has spent nine

days in an aircraft assessing

the damage and

covering more

than 6,000 miles

to inspect 1,036

reefs, retracing

surveys he did

after previous

bleaching.

It is too early to

know yet how

much coral will die

as a result of the lat-

est event, but Pro-

fessor Hughes told

the Australian

Broadcasting Cor-

poration that he

feared the worst,

particularly in the

southern part of the reef. “The south-

ern bleaching was very severe and we

were most concerned about the south

because of the naivety of the corals that

are there,” he said. “They hadn’t

bleached before, which means there are

more corals and more of the corals that

are particularly susceptible to heat

stress.”

In 2016 and 2017 about half the coral

on the reef was estimated to have died.

In previous events the areas hit hardest

were in the remote northern

stretches, around Lizard Island, 1,000

miles north of Brisbane, and beyond.

The southern and central reef had

mostly been spared. “For the first time,

the Barrier Reef has bleached in all

three major regions: in the north, in the

central region and in the southern re-

gions,” Professor Hughes said.

“Quite frankly, [I’m] astonished by

the speed of these changes,” he said.

“What we’re seeing on the Great

Barrier Reef now is a huge transforma-

tion in the mix of species [of coral].

We’re seeing less and less of the heat-

sensitive, susceptible species — the so-

called losers — compared with the

tougher corals, which are persisting.

The Great Barrier Reef is transitioning

250 miles

Severe

coral

bleaching

2016

2017

2020

Cairns

Mackay

North West

Island

Townsville

AUSTRALIA

Great Barrier

Reef Marine Park

400 species

of coral

The Great Barrier Reef is home to more than 1,500 fish species, many of which

rely on branching coral for habitat, but that type struggles to survive bleaching

eef“Th

wereintheremote th

T

r

Marine life at risk from biggest

bleaching of Great Barrier Reef

Australia

Bernard Lagan Sydney

JAMES COOK UNIVERSITY AUSTRALIA/AFP/GETTY IMAGES

First farmers in Britain were horsemen from the Steppes

during which societies began forming

permanent settlements and farming

animals. The migration and the

changes it brought with it reached as far

northwest as the British Isles.

The second wave of migrants were

the Yamnaya people from the Pontic

steppe, between the Dniester and Ural

rivers in modern-day Ukraine, who

are believed to have brought horse-

herding and early Indo-European

languages with them as they moved

west into Europe at the start of the

Bronze Age, about 5,000 years ago.

This wave penetrated farther than

the previous migration from Anatolia,

probably because the Yamnaya trav-

elled with horses, but also, possibly,

because some land had already been

cleared and cultivated during the Neo-

lithic era, making it easier to travel.

The effects of this second wave of

migration reached as far as Scandin-

avia and coincided with the beginning

of more widespread deforestation

across much of Europe.

Relics of the ancient Yamnaya civili-

sation have been discovered across

Ukraine and southern Russia, and

include pots, jewellery and wheeled

carts. Their name is derived from the

Russian word for pit, and refers to their

culture of burial. The dead were buried

in simple graves, usually on their sides

with knees bent, and covered with

ochre. In Europe this tradition

developed into the catacomb culture.

The Yamnaya lived mostly as

inhabitants were wiped out within a few

centuries.

Previous genetic studies have shown

that modern Europeans are descended

from nomads who came from Africa

and the east, but this is the first time

that the impact of migration on land

usage and the environment in Europe

has been studied.

Ancient DNA is harvested from

archaeological finds and the microbes

in the soil surrounding them. The

researchers compared hundreds of

samples to map ancient migration

patterns, and compared them to estab-

lished pollen records going back nearly

11,000 years. They also simulated the

climate and how it has changed over

the millennia.

Turkey

Hannah Lucinda Smith Istanbul

TURKEY

UKRAINE

UK

SWEDEN

FRANCE

SPAIN

3,000BC

6,500BC