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What the sources say

Desert LocustSchistocerca gregaria

Every figure, record and mechanism on the Desert Locust profile was written from a source, and this is the working table behind it: 43 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Food and Agriculture Organization of the United Nations

Desert Locust. Food and Agriculture Organization of the United Nations.

The page saysA shy loner that turns into a swarming crop-eater when it gets crowded
The source saysIn response to environmental stimuli, dense and highly mobile Desert Locust swarms can form. They are ravenous eaters who consume their own weight per day, targeting food crops and forage.Note: tagline; 'crowded' is the NASA claim below
The page saysUsually the semi-arid and arid deserts of Africa, the Near East and South-West Asia
The source saysDuring quiet periods (known as recessions) Desert Locusts are usually restricted to the semi-arid and arid deserts of Africa, the Near East and South-West AsiaNote: stats.habitat
The page saysVegetation, including crops, forage and noxious weeds
The source saysThey are ravenous eaters who consume their own weight per day, targeting food crops and forage.Note: stats.diet
The page saysIn its gregarious phase it turns social, changes colour and shape, and joins a swarm
The source saysIn response to environmental stimuli, dense and highly mobile Desert Locust swarms can form.
The page saysA square kilometre of swarm can hold up to 80 million adults
The source saysJust a single square kilometer of swarm can contain up to 80 million adults
The page saysThey target food crops and forage
The source saystargeting food crops and forage
The page saysDesert locusts live for 3 months
The source saysDesert Locust live for 3 months
The page saysEggs hatch after two weeks, and the wingless young, called hoppers, become winged adults after 6 weeks
The source sayseggs hatch after two weeks, hoppers fledge and become adults after 6 weeks
The page saysAdults take at least a month to mature and be ready to lay eggs
The source saysadults take at least one month to mature and be ready to lay eggs
The page saysNumbers can grow 20 times in three months
The source saysThere can be an exponential increase in locust numbers with every new generation of breeding: a 20 time increase in their numbers after three months
The page saysIn quiet periods, called recessions
The source saysDuring quiet periods (known as recessions)
The page saysthat get under 200 mm of rain a year
The source saysthat receive less than 200 mm of rain annually
The page saysThat belt covers about 16 million square kilometres in about 30 countries
The source saysThis is an area of about 16 million square kilometres, consisting of about 30 countries.
The page saysFemales lay their eggs in moist sandy soil, and rain helps them survive and breed
The source sayslay eggs in moist sandy soil; rainfall is conducive to Desert Locust survival and reproduction
The page saysUp to 150 km. Desert locusts fly in daylight and travel downwind
The source saysDesert Locust fly during the day downwind for up to 150 km in a day.Note: faq
The page saysBy FAO's reckoning, a swarm covering one square kilometre has the potential to eat as much food in a day as 35,000 people
The source saysA 1 km2 swarm has the potential to eat the same amount of food in one day as 35,000 people.Note: faq
The page sayslarge swarms are a major threat to food security and rural livelihoods
The source saysLarge swarms pose a major threat to food security and rural livelihoods.Note: faq

Source
02

NASA Earth Observatory

Locust! NASA Earth Observatory.

The page saysA shy loner that turns into a swarming crop-eater when it gets crowded
The source saysIn one phase, it’s reclusive and solitary, going out of its way to avoid coming into contact with another of its kindNote: tagline; crowd trigger in the next claim
The page saysA shy loner that turns into a swarming crop-eater when it gets crowded
The source saysThe forced physical contact brought about when numerous locusts descend on a dwindling food supply causes the animals’ hind legs to bump up against one another. This jostling triggers a cascade of metabolic and behavioral changes
The page saysVegetation, including crops, forage and noxious weeds
The source sayssubsisting on even the most noxious weeds when necessaryNote: stats.diet
The page saysSwitches from loner to swarm member when crowded
The source saystransformation from “go it alone” to “one of the crowd.”Note: stats.superpower
The page saysThe desert locust has two phases
The source saysThe desert locust has two phases.
The page saysIn its solitary phase it is reclusive, goes out of its way to avoid others of its kind and migrates only at night
The source saysIn one phase, it’s reclusive and solitary, going out of its way to avoid coming into contact with another of its kind and migrating only at night.
The page saysIn its gregarious phase it turns social, changes colour and shape, and joins a swarm
The source saysit undergoes explosive population growth, changes color and shape, and becomes more tolerant of others, more social, or gregarious.
The page saysWhen locusts are forced together, their hind legs bump against one another, and that jostling sets off a cascade of metabolic and behavioural changes
The source saysThe forced physical contact brought about when numerous locusts descend on a dwindling food supply causes the animals’ hind legs to bump up against one another. This jostling triggers a cascade of metabolic and behavioral changes
The page saysThey develop yellow and black warning colours, most strongly in the juveniles
The source saysThey develop a yellow and black warning coloration—most pronounced in the juveniles
The page saysTheir bodies become shorter, and they give off a perfume of hormones that attracts them all to the same location
The source saysTheir bodies become shorter, and they give off a perfume of hormones that causes them all to be attracted to the same location
The page saysEach locust weighs about 2 grams and can eat its own body weight in vegetation every day
The source saysWith each insect capable of eating its own body weight (about 2 grams, or .07 ounces) in vegetation each dayNote: mass is NASA's; scope is the species
The page sayscan survive on even the most noxious weeds when they must
The source sayssubsisting on even the most noxious weeds when necessary
The page saysA single swarm can cover 1,200 square kilometres
The source saysA single swarm can cover 1200 square kilometers (460 square miles)
The page saysAs many as 60 countries can be affected
The source saysAs many as 60 countries can be affected.
The page saysthe wingless young, called hoppers
The source saysthe newly hatched “hoppers,” as the young, wingless insects are called
The page saysThey are one species, Schistocerca gregaria, in two phases
The source saysthe standoffish locust of the recession years was the same species of insect that exploded out of the desertNote: faq
The page saysScientists did not realise that until 1921
The source saysit wasn’t until 1921 that scientists even became aware that the standoffish locust of the recession years was the same species of insectNote: faq
The page saysCrowding turns a desert locust into a swarm member
The source saysThe forced physical contact brought about when numerous locusts descend on a dwindling food supply causes the animals’ hind legs to bump up against one another. This jostling triggers a cascade of metabolic and behavioral changesNote: vibe.reason; same quote as the body claim "When locusts are forced together, their hind legs bump again"
The page sayshind legs bumping against one another set off the change
The source saysThe forced physical contact brought about when numerous locusts descend on a dwindling food supply causes the animals’ hind legs to bump up against one another. This jostling triggers a cascade of metabolic and behavioral changesNote: vibe.reason; same quote as the body claim "A shy loner that turns into a swarming crop-eater when it ge"

Source
03

Anstey et al. 2009

Anstey et al. (2009). Serotonin Mediates Behavioral Gregarization Underlying Swarm Formation in Desert Locusts. Science.

The page saysserotonin is both necessary for behavioural gregarization to occur and sufficient to induce it
The source saysbeing both necessary if behavioral gregarization is to occur and sufficient to induce it

Source
04

Bennet-Clark 1975

Bennet-Clark (1975). The energetics of the jump of the locust Schistocerca gregaria. Journal of Experimental Biology.

The page saysFor an adult male, one jump takes 9 millijoules of energy
The source saysThe jump of adult male locusts requires an energy of 9 mJ
The page saysthe major part of that energy is stored before the leap
The source saysThe major part of the jump energy is stored before the jump.
The page saysThe push itself lasts 25 to 30 milliseconds
The source saysThe jump impulse lasts 25-30 msec.
The page saysTheir jump runs on a spring
The source saysThe anatomy of the metathoracic leg is redescribed with particular reference to storage of energy in cuticular elements and the way in which the stored energy is used in jumping.Note: figure; the spring is the stored elastic energy
The page saysthe locust reaches 3.2 metres per second
The source saysA velocity of 3.2 m.sec-1 is reached after a peak acceleration of 180 m.sec-2.

Source
05

Simpson, McCaffery & Hägele 1999

Simpson, McCaffery & Hägele (1999). A behavioural analysis of phase change in the desert locust. Biological Reviews.

The page saysfemales use their experience of being crowded to predict whether their young will hatch into a crowd, and change how the embryos develop to match
The source saysFemale locusts use their experience of the extent and recency of being crowded to predict the probability that their offspring will emerge into a high-density population, and alter the development of their embryos accordingly

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.