Trinidadian guppies have individual personalities, new research


This 2014 video says about itself:

Sustainable Innovation Initiatives (SII) creates bridges between research, business, industry, tourism and educators to make ecological sustainability a priority for societies in tropical forest ecosystems. Our upcoming documentary series helps us accomplish this goal by reaching many people through video.

“Home of the Guppy” is our first episode. It highlights unique features of research in the Northern Range of Trinidad and grassroots efforts in habitats critical to this watershed and communities that use it.

Home of the Guppy Summary: Streams in Trinidad’s Northern Mountain range have been epicenters for breakthroughs in evolutionary theory over the last five decades.

A unique combination of isolation, species-diversity and system-replication has created a “natural laboratory” like no other in the world. These unique conditions have allowed scientists to examine every guppy in multiple wild populations for as many as 15 generations. Guppy studies in Trinidad have produced one of the most detailed multi-generation data collections ever compiled in a wild vertebrate. Results from these studies are reshaping longstanding views of evolutionary theory.

From the University of Exeter in England:

Fish have surprisingly complex personalities

Tiny fish called Trinidadian guppies have individual ‘personalities,’ new research shows

September 25, 2017

Scientists from the University of Exeter studied how guppies behaved in various situations, and found complex differences between individuals.

The researchers tested whether differences could be measured on a “simple spectrum” of how risk-averse or risk-prone guppies were. But they found variations between individuals were too complicated to be described in this way.

“The idea of a simple spectrum is often put forward to explain the behaviour of individuals in species such as the Trinidadian guppy,” said Dr Tom Houslay, of the Centre for Ecology and Conservation (CEC) on the University of Exeter’s Penryn Campus in Cornwall.

“But our research shows that the reality is much more complex. “For example, when placed into an unfamiliar environment, we found guppies have various strategies for coping with this stressful situation — many attempt to hide, others try to escape, some explore cautiously, and so on.

“The differences between them were consistent over time and in different situations. So, while the behaviour of all the guppies changed depending on the situation — for example, all becoming more cautious in more stressful situations — the relative differences between individuals remained intact.”

The study, published in the journal Functional Ecology, examined the “coping styles” of guppies in conditions designed to cause varying levels of stress.

Mild stress was caused by transferring fish individually to an unfamiliar tank, and higher levels of stress were caused by adding models of predatory birds or fish.

The presence of predators had an effect on “average” behaviour — making all of the guppies more cautious overall — but individuals still retained their distinct personalities.

Professor Alastair Wilson, also from the CEC at the University of Exeter, added: “We are interested in why these various personalities exist, and the next phase of our research will look at the genetics underlying personality and associated traits.

“We want to know how personality relates to other facets of life, and to what extent this is driven by genetic — rather than environmental — influences.

“The goal is really gaining insight into evolutionary processes, how different behavioural strategies might persist as species evolve.”

The paper is entitled: “Testing the stability of behavioural coping style across stress contexts in the Trinidadian guppy.”

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London Grenfell Tower disaster damages mental health


London, England: Grenfell survivors and local residents outside Kensington & Chelsea Council Town Hall demanding the resignation of the council

From daily News Line in Britain:

Saturday, 23 September 2017

GRENFELL INFERNO! – unprecedented trauma

THE GRENFELL Tower disaster triggered a mental health crisis of an ‘unprecedented’ scale, a leading doctor has said 100 days on from the fire.

NHS data shows 457 adults have been flagged as being in ‘urgent need’ of treatment for post-traumatic stress disorder, while 39 children are also receiving specialist mental health care.

Survivors and nearby witnesses of the June 14 inferno, which left so many dead, are considered to have a 50% chance of developing the disorder, according to health service modelling. Those mentally scarred by the tragedy report suffering from flashbacks and sleeplessness, which can be triggered by the sight of the tower’s wreckage, clinicians say.

Dr Alastair Bailey, the clinical psychological lead at the NHS Grenfell Tower Trauma Service, said the impact of the fire is unlike anything seen before by the health service. He said: ‘It is unprecedented, I don’t think we have experienced anything like it. We had similar events that have been large-scale, traumatic events that have occurred in the UK.

‘We think about the London bombings, the terror attack in Tunisia which affected British nationals and other events over the years, but nothing has affected a community like this for a number of years.

‘Similar events have occurred that have affected one community, things like the Hillsborough football disaster, the Aberfan disaster in Wales, similar in that they affected one community a number of years ago.

‘In terms of a trauma response, managing an NHS response to trauma, we are using ideas and protocols and procedures that were developed after London bombings and other similar events, which are quite different.’

A staff of around 170 mental health workers, soon to be more than 200, have been tasked with supporting the west London community, holding specialist surgeries and knocking on doors to ensure support is given to those affected.

Currently, 201 patients are receiving treatment from mental health services in the area and eight people have completed treatment, said the Central and North West London NHS Trust (CNWL). But, with more than 150 families from Grenfell Tower or Grenfell Walk still in hotels, many people grappling with trauma are reluctant to begin receiving treatment. CNWL, the main service responding to the disaster, said 20% of patients referred to them decline further treatment, often citing their living arrangements as the problem.

As the neighbourhood marks another grim milestone since the country’s most costly tragedy in a generation, just five households left destitute by the blaze have found permanent accommodation.

See also here.

Diane Abbott: Grenfell Tower fire ‘direct consequence of deregulation, privatisation and outsourcing’. Shadow Home Secretary calls for immigration amnesty for survivors, and says Labour would recruit 3,000 firefighters: here.

DEREGULATION and privatisation are to blame for the Grenfell Tower inferno and justice must be served for the victims and survivors, Diane Abbott said at the Labour conference yesterday. The shadow home secretary insisted the fire, which was fuelled by combustible cladding installed on the exterior of the 24-storey west London housing block, was a direct result of Tory-led deregulation of fire standards and inspection, privatisation and outsourcing: here.

New crustacean discovery in Dutch Zeeland


Caprella equilibra, photo by Brian Prins

This photo by Brian Prins shows a crustacean species, new for the Netherlands: Caprella equilibra.

Its size is only four millimeter.

It was found near Borssele in Zeeland province.

Cambrian trilobites from China, new research


This American Museum of Natural History video from the USA says about itself:

Niles Eldredge: Trilobites and Punctuated Equilibria

17 December 2015

In the late 1960s, Curator Emeritus Niles Eldredge was a graduate student with a passion for trilobite eyes. He had been taught to expect slow and steady change between the specimens of these Devonian arthropods he collected for his dissertation. Only his trilobites were doing one of two things: staying the same, or evolving in leaps.

Several years later, Eldredge, along with co-author Stephen Jay Gould, turned his observations into a theory known as “punctuated equilibria”: the idea that species stay relatively the same, or at equilibrium, throughout the fossil record save for rare bursts of evolutionary change.

A former Chairman and Curator of Paleontology at the American Museum of Natural History, Eldredge remains at the hub of evolutionary discussion and debate, as well as one of the world’s experts on trilobites, specializing in mid-Paleozoic phacopids. He has also analyzed the relationship between global extinctions of the geologic past and the present-day biodiversity crisis, as well as the general relationship between extinction and evolution.

Learn more about Trilobites: here.

From the American Museum of Natural History in the USA:

Early trilobites had stomachs, new fossil study finds

Remarkable Chinese specimens contradict previous assumptions about trilobite digestive systems and evolution

September 21, 2017

Exceptionally preserved trilobite fossils from China, dating back to more than 500 million years ago, have revealed new insights into the extinct marine animal’s digestive system. Published today in the journal PLOS ONE, the new study shows that at least two trilobite species evolved a stomach structure 20 million years earlier than previously thought.

“Trilobites are one of the first types of animals to show up in large numbers in the fossil record,” said lead author Melanie Hopkins, an assistant curator in the Division of Paleontology at the American Museum of Natural History. “Their exoskeletons were heavy in minerals, and so they preserved really well. But like all fossils, it’s very rare to see the preservation of soft tissues like organs or appendages in trilobites, and because of this, our knowledge of the trilobite digestive system comes from a small number of specimens. The new material in this study really expands our understanding.”

Trilobites are a group of extinct marine arthropods — distantly related to the horseshoe crab — that lived for almost 300 million years. They were extremely diverse, with about 20,000 species, and their fossil exoskeletons can be found all around the world. Most of the 270 specimens analyzed in the new study were collected from a quarry in southern Kunming, China, during an excavation led by Hopkins’ co-author, Zhifei Zhang, from Northwest University in Xi’an.

Previous research suggests that two body plans existed for trilobite digestive systems: a tube that runs down the length of the trilobite’s body with lateral digestive glands that would have helped process the food; or an expanded stomach, called a “crop,” leading into a simple tube with no lateral glands. Until now, only the first type had been reported from the oldest trilobites. Based on this, researchers had proposed that the evolution of the crop came later in trilobite evolutionary history and represented a distinct type of digestive system.

The Chinese trilobite fossils, about 20 percent of which have soft tissue preservation, are dated to the early Cambrian, about 514 million years ago. Contradictory to the previously proposed body plans, the researchers identified crops in two different species within this material. In addition, they found a single specimen that has both a crop and digestive glands — suggesting that the evolution of trilobite digestive systems is more complex than originally proposed.

The study backs up an earlier announcement made by a separate research team, which found evidence for the unusual crop and gland pairing in a single juvenile trilobite specimen from Sweden from the late Cambrian. But the Chinese material presents the oldest example of this complex digestive system in a mature trilobite, wiping away doubts that the dual structures might just be part of the animal’s early development.

“This is a very rigorous study based on multiple specimens, and it shows that we should start thinking about this aspect of trilobite biology and evolution in a different way,” Hopkins said.

Dinosaur extinction and bird evolution


This American Museum of Natural History video from the USA says about itself:

18 March 2016

This spellbinding animation from the Museum’s new exhibition “Dinosaurs Among Us” traces the evolutionary transition from dinosaurs to birds.

Based on recent scientific research that examines fossils using new technologies, the transformation story unfolds as low-polygonal silhouettes of dinosaurs morph from ground-dwelling animals into flight-capable birds. The mass extinction that erased most dinosaurs 65 million years ago left a few bird lineages unscathed. Within only 15 million years all of our familiar bird groups were flourishing. These extraordinary living dinosaurs provide a vivid link to the ancient past. The Museum’s new exhibition, “Dinosaurs Among Us,” explores the continuities between living dinosaurs—birds—and their extinct ancestors, showcasing remarkable new evidence for what scientists now call one of the best-documented evolutionary transitions in the history of life.

From Cornell University in the USA:

Dino-killing asteroid’s impact on bird evolution

September 21, 2017

Human activities could change the pace of evolution, similar to what occurred 66 million years ago when a giant asteroid wiped out the dinosaurs, leaving modern birds as their only descendants. That’s one conclusion drawn by the authors of a new study published in Systematic Biology.

Cornell University Ph.D. candidate Jacob Berv and University of Bath Prize Fellow Daniel Field suggest that the meteor-induced mass extinction (a.k.a. the K-Pg event) led to an acceleration in the rate of genetic evolution among its avian survivors. These survivors may have been much smaller than their pre-extinction relatives.

“There is good evidence that size reductions after mass extinctions may have occurred in many groups of organisms,” says Berv. “All of the new evidence we have reviewed is also consistent with a Lilliput Effect affecting birds across the K-Pg mass extinction.” Paleontologists have dubbed this phenomenon the “Lilliput Effect” — a nod to the classic tale Gulliver’s Travels.

“Smaller birds tend to have faster metabolic rates and shorter generation times,” Field explains. “Our hypothesis is that these important biological characters, which affect the rate of DNA evolution, may have been influenced by the K-Pg event.”

The researchers jumped into this line of inquiry because of the long-running “rocks and clocks” debate. Different studies often report substantial discrepancies between age estimates for groups of organisms implied by the fossil record and estimates generated by molecular clocks. Molecular clocks use the rate at which DNA sequences change to estimate how long ago new species arose, assuming a relatively steady rate of genetic evolution. But if the K-Pg extinction caused avian molecular clocks to temporarily speed up, Berv and Field say this could explain at least some of the mismatch. “Size reductions across the K-Pg extinction would be predicted to do exactly that,” says Berv.

“The bottom line is that, by speeding up avian genetic evolution, the K-Pg mass extinction may have temporarily altered the rate of the avian molecular clock,” says Field. “Similar processes may have influenced the evolution of many groups across this extinction event, like plants, mammals, and other forms of life.”

The authors suggest that human activity may even be driving a similar Lilliput-like pattern in the modern world, as more and more large animals go extinct because of hunting, habitat destruction, and climate change.

“Right now, the planet’s large animals are being decimated — the big cats, elephants, rhinos, and whales,” notes Berv. “We need to start thinking about conservation not just in terms of functional biodiversity loss, but about how our actions will affect the future of evolution itself.”

Some herbivorous dinosaurs really omnivorous?


This 2012 video from the USA says about itself:

Maiasaura: Learn About Dinosaurs with World Book’s Professor Nick

Maiasaura was a large plant-eating dinosaur noted for its nesting behavior. Its name means good mother lizard, though dinosaurs were not lizards. Evidence suggests that its hatchlings were completely dependent on their parents for food and protection. Maiasaura lived about 75 to 80 million years ago in the area of what is now Montana. It belonged to a group known as duckbilled dinosaurs or hadrosaurids. These dinosaurs ate plants using a beak that somewhat resembled a duck’s bill.

By Carolyn Gramling, 9:00am, September 21, 2017:

Shhhh! Some plant-eating dinos snacked on crunchy critters

Crustacean shells discovered in fossilized poop reveal diet secrets of ancient herbivores

Some dinosaurs liked to cheat on their vegetarian diet.

Based on the shape of their teeth and jaws, large plant-eating dinosaurs are generally thought to have been exclusively herbivorous. But for one group of dinosaurs, roughly 75-million-year-old poop tells another story. Their fossilized droppings, or coprolites, contained tiny fragments of mollusk and other crustacean

Mollusks and crustaceans are two different groups.

shells along with an abundance of rotten wood, researchers report September 21 in Scientific Reports. Eating the crustaceans as well as the wood might have given the dinosaurs an extra dose of nutrients during breeding season to help form eggs and nourish the embryos.

“Living herd animals do occasionally turn carnivore to fulfill a particular nutritional need,” says vertebrate paleontologist Paul Barrett of the Natural History Museum in London. “Sheep and cows are known to eat carcasses or bone when they have a deficiency in a mineral such as phosphorus or calcium, or if they’re pregnant or ill.” But the discovery that some plant-eating dinos also ate crustaceans is the first example of this behavior in an extinct herbivore, says Barrett, who was not involved in the new study.

Ten years ago, paleoecologist Karen Chin of the University of Colorado Boulder described finding large pieces of rotted wood in dino dung. The coprolites were within a layer of rock in Montana, known as the Two Medicine Formation, dating to between 80 million and 74 million years ago. That layer also contained numerous fossils of Maiasaura, a type of large, herbivorous duck-billed dinosaur, or hadrosaur (SN: 8/9/14, p. 20).

Chin wondered whether the wood itself was the dino’s real dietary target. “The coprolites in Montana were associated with the nesting grounds of the Maiasaura,” she says. “I suspected that the dinosaurs were after insects in the wood. But I never found any insects in the coprolites there.”

Her hunch wasn’t too far off. Now she’s found evidence of some kind of crustaceans in dino poop. The new evidence comes from an 860-meter-thick layer of rock in Utah known as the Kaiparowits Formation, which dates to between 76.1 million and 74 million years ago. Ten of the 15 coprolites that Chin and her team examined contained tiny fragments of shell that were scattered throughout the dung. They were too small to identify by species, and may have been crabs, insects or some other type of shelled animal, Chin says. Based on the scattering of shell fragments, the animals were certainly eaten along with the wood rather than being later visitors to the dung heap.

Since bones from hadrosaurs are especially abundant in the Kaiparowits Formation, Chin suspects those kinds of dinos deposited the dung. Other large herbivores, such as three-horned ceratopsians and armored ankylosaurs, also roamed the area (SN: 6/24/17, p. 4).

The crustacean diet cheat may have been a seasonal event, related perhaps to breeding to obtain extra nutrients, Chin and colleagues say.

But how often — or why — the dinosaurs ate the shelled critters is hard to prove from the fossil dung alone, Barrett says. Herbivore coprolites are rare in the fossil record because a diet of leaves and other green plant material doesn’t leave a lot of hard material to preserve (unlike bones in carnivore dung). Coprolites with crustaceans, on the other hand, are more likely to get fossilized — and that preferential preservation might make it appear that this behavior was more frequent than it actually was. “These kinds of things give neat snapshots of specific behaviors that those animals are doing at any one time,” he adds. “But it’s difficult to build that into a bigger picture.”