Should we be drinking milk?

In recent years, there's been a lot of debate about whether drinking the milk of other animals is good for us. But how do the arguments for and against drinking dairy milk stack up?

For a more in-depth look, see BBC Future’s ‘Why humans have evolved to drink milk’ and 'Is it better to drink cow’s milk or a dairy-free alternative?'.

Animation by Alex Kessling

Cutting food and carbon waste-lines for healthy climate

Reducing food waste and changing the way people consume calories will help deliver a sustainable food system and reduce emissions, a study suggests.

An estimate one third of all food produced remains uneaten

The global demand for food could more than double by the middle of the century, yet an estimated one third of produce is lost or wasted each year.

By cutting this waste will help food security and reducing agriculture's climate burden, the researchers added.

The findings appear in the journal Environmental Science & Technology.

As the global human population is set to reach in excess of nine billion people by the middle of this century, up from the current seven billion, the importance of reducing food loss and waste in order to deliver food security is well documented.

However, a team of scientists have also considered what steps need to be taken to tackle food production's contribution to global carbon emissions.

Shifts in lifestyle and diet is increasing the global impact of the food sector

Prof Jurgen Kropp from the Potsdam Institute for Climate Impact Research, Germany, one of the study's co-authors said that previous studies had highlighted that "agriculture was playing an increasingly important role when it came to carbon dioxide emissions".

"We have worldwide lifestyle changes where people are moving towards a meat-rich diet and we need more food, of course," he told BBC News.

"The more rich a country becomes, there is a move towards more meat-rich diets and, of course, more calorie-rich diets.

"For one calorie of meat, you have to utilise one to eight calories of cereal. It is an inefficient form of food production," he observed.

"On the other hand, rich countries are wasting more food. A lot of the food we are producing at the moment, we do not see on our plates."

Prof Kropp added that this trend was projected to have a considerable impact on the global carbon budget by the middle of the 21st Century.

They calculated that about 10% of global greenhouse gas emissions from agriculture could be traced back to food waste by 2050.

However, the team examined past datasets and used future scenarios to identify pathways that could deliver improvements in food security and CO2 emissions.

As people around the globe shift to more meat-rich diets, emissions from agriculture continue to rise

The team observed: "The global food requirement changed from 2,300 [calories per person each day] to 2,400 [calories per person each day] during the past 50 years, while the food surplus grew from 310 [calories per person each day] to 510 [calories per person each day]."

Over the same period, the team found that greenhouse gas emissions associated with food surplus increased from 130 million tones of CO2 equivalent per year to 530 million tonnes - an increase of more than 300%.

Future scenarios did not make comfortable reading. They calculated that emissions associated with the food wasted may "increase tremendously" to up to 2.5 giga-tonnes of CO2 equivalent per year.

Prof Kropp added: "As many emerging economies like China or India are projected to rapidly increase their food waste as a consequence of changing lifestyle, increasing welfare and dietary habits towards a larger share of animal-based products, this could over proportionally increase greenhouse-gas emissions associated with food waste [while] undermining efforts for an ambitious climate protection.

"Avoiding food loss could pose a leverage to various challenges at once, reducing environmental impacts of agriculture, saving resources used in food production, and enhance local, regional, and global food security."

From BBC News Science / Environment

Global fishing catch significantly under-reported, says study

The amount of fish taken from the world's oceans over the last 60 years has been underestimated by more than 50%, according to a new study.

Global fish take based on official figures underestimates the actual catch size according to this study

Researchers say that official estimates are missing crucial data on small scale fisheries, illegal fishing and discarded by-catch.

The authors argue that global fishing catches are now declining rapidly because stocks have been exhausted.

But other researchers have questioned the reliability of the new study.

The UN's Food and Agriculture Organisation (FAO) is the body that collates global statistics on fishing from countries all over the world.

According to their official figures, the amount of fish caught has increased steadily since 1950 and peaked at 86 million tonnes in 1996 before declining slightly to around 77 million tonnes in 2010.

But researchers from the University of British Columbia argue that the official figures drastically under-report the true scale of fishing.

They argue that the figures submitted to the FAO are mainly from large scale "industrial" fishing activities and do not include small scale commercial fisheries, subsistence fisheries as well as the discarded by-catch and estimates for illegal fishing.

The scientists say their "catch reconstruction" method give a far more accurate picture of the scale of the impacts of fishing around the world.

They say that reconstructed catches, that include estimates and data on the under-reported activities, show that the world took 53% more fish from the seas than the official figures indicate.

They argue that around 32 million tonnes of fish go unreported every year - more than the weight of the entire US population.

"The catches are all underestimated," said lead author Prof Daniel Pauly.

"The FAO doesn't have a mandate to correct the data that they get - and the countries have the bad habit of reporting only what they see - if they don't have people who report on a given fishery then nothing is reported. The result of this is a systematic underestimation of the catch and this can be very high, 200-300% especially in small island states, in the developed world it can be 20-30%."

Prof Pauly gave the Bahamas as an example where there was no reporting of fish caught by small scale fishers. But when the researchers dug a little deeper and went to the big hotels and resorts, they found invoices from small scale fishermen who sold their catch directly.

Not only have more fish been taken from the seas than have been reported say the authors, but the decline in fish caught since the mid 1990s has been far greater than the official figures show.

A graph showing the differences between the official figures and the reconstructed catch

From BBC Science/Environment

Read the whole article

Plastic in oceans 'threatens food chain'

As England prepares to introduce a charge for plastic bags, science editor David Shukman reports on the possible threat to the food chain, by the plastics broken down into tiny fragments in our oceans.

Tests by the Plymouth Marine Laboratory have shown that when minuscule particles of plastic are in the water, the creatures at the bottom of the food chain do ingest them.

An estimated eight million tonnes of plastic waste is added to the oceans every year.(BBC News)

Saving the sturgeon

The most expensive fish on Earth

Sturgeon is the common name used for some 25 species of fish in the family Acipenseridae, including the genera Acipenser, Huso, Scaphirhynchus, and Pseudoscaphirhynchus. The term includes over 20 species commonly referred to as sturgeon and several closely related species that have distinct common names, notably sterlet, kaluga, and beluga. Collectively, the family is also known as the true sturgeons. Sturgeon is sometimes used more exclusively to refer to the species in the two best-known genera, Acipenser, and Huso. Sturgeons have been referred to as "primitive fishes" because their morphological characters have remained relatively unchanged since the earliest fossil record.

Sturgeons are native to subtropical, temperate and sub-Arctic rivers, lakes and coastlines of Eurasia and North America. They are distinctive for their elongated bodies, lack of scales, and occasional great size: sturgeons ranging from 7–12 feet (2-3½ m) in length are common, and some species grow up to 18 feet (5.5 m). Most sturgeons areanadromous bottom-feeders, spawning upstream and feeding in river deltas and estuaries. While some are entirely freshwater, a very few venture into the open ocean beyond near coastal areas.

Several species of sturgeons are harvested for their roe, which is made into caviar — a luxury food which makes some sturgeons pound for pound the most valuable of all harvested fish. Because they are slow-growing and mature very late in life, they are particularly vulnerable to exploitation and to other threats, including pollution and habitat fragmentation. Most species of sturgeons are currently considered to be at risk of extinction, making them more critically endangered than any other group of species.

in Wikipedia

Food waste reduction could help feed world's starving

One third of all food produced is wasted, the UN estimates

"If food was as expensive as a Ferrari, we would polish it and look after it."

Instead, we waste staggering amounts.

So says Professor Per Pinstrup-Andersen, head of an independent panel of experts advising the UN's Food and Agricultural Organization on how to tackle the problem.

Some 40% of all the food produced in the United States is never eaten. In Europe, we throw away 100 million tonnes of food every year.

And yet there are one billion starving people in the world.

The FAO's best guess is that one third of all food produced for human consumption is lost or wasted before it is eaten.

Food waste

33%

of all food is wasted
$750bn

cost of waste food

• 28% of farmland grows food that will be thrown away
• 6-10% of greenhouse gases come from waste food
• 39% of household food waste is fruit and vegetables

Source: UN/FAO

SPL

The latest report from the expert panel of the UN Committee on World Food Security concludes that food waste happens for many different reasons in different parts of the world and therefore the solutions have to be local.

Take Chris Pawelski, a fourth generation onion farmer from the US. Mr Pawelski has spent months growing onions in the rich, black soil of Orange County, New York, but the supermarkets he sells to will only accept onions of certain size and look.

READ THE WHOLE ARTICLE

From BBC-Busines