Corals eating jellyfish, video


This 7 August 2018 video says about itself:

Corals Collaborating to Eat Jellyfish: First-Ever Video | National Geographic

Filmed for the first time, Astroides calycularis coral trap and devour “mauve stinger” jellyfish. In the western Mediterranean Sea, the orange coral forms colonies of small organisms called polyps. The polyps are connected, and together act as a single organism with multiple tiny mouths.

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Peppered moths and evolution, new study


This 1 June 2016 video says about itself:

Insect icon Peppered moth mystery solved: BBC News

From the University of Exeter in England:

Study confirms truth behind ‘Darwin‘s moth’

August 17, 2018

Scientists have revisited — and confirmed — one of the most famous textbook examples of evolution in action.

They showed that differences in the survival of pale and dark forms of the peppered moth (Biston betularia) are explained by how well camouflaged the moths are to birds in clean and polluted woodland.

“Industrial melanism” — the prevalence of darker varieties of animals in polluted areas — and the peppered moth provided a crucial early example supporting Darwin‘s theory of evolution by natural selection, and has been a battleground between evolutionary biologists and creationists for decades.

The common pale form of the moth is camouflaged against lichen growing on tree bark. During the Industrial Revolution — when pollution killed lichen and bark was darkened by soot — a darker-winged form emerged in the UK.

Later, clean air legislation reduced soot levels and allowed lichen to recover — causing a resurgence of pale peppered moths.

The example has been well supported by many studies, but nobody had ever tested how well camouflaged the moths were to the vision of their key predators — birds — and how their camouflage directly influenced survival.

Now scientists at the University of Exeter have shown that, to the vision of birds, pale moths are indeed more camouflaged against lichen-covered trees than dark moths — making pale moths less likely to be eaten by birds in unpolluted woodland and giving them an evolutionary advantage.

“This is one of the most iconic examples of evolution, used in biology textbooks around the world, yet fiercely attacked by creationists seeking to discredit evolution”, said Professor Martin Stevens, of the Centre for Ecology and Conservation on the University of Exeter’s Penryn Campus in Cornwall.

“Remarkably, no previous study has quantified the camouflage of peppered moths, or related this to survival against predators in controlled experiments.

“Using digital image analysis to simulate bird vision and field experiments in British woodland, we compared how easily birds can see pale and darker moths, and ultimately determine their predation risk.

“Our findings confirm the conventional story put forward by early evolutionary biologists — that changes in the frequency of dark and pale peppered moths were driven by changes in pollution and camouflage.”

Most birds can perceive ultraviolet light — invisible to human eyes — and see a greater range of colours than humans, and the Exeter scientists analysed how well pale and dark moths matched lichen-covered and plain tree bark, as seen by birds.

To do this, they used museum specimens including some from the collections of Bernard Kettlewell, who conducted famous research on the evolution of the species in the 1950s.

The researchers also created artificial moths, baited them with food and observed predation rates in UK woodland, mostly in Cornwall.

“Through a bird’s eyes, the pale peppered moths more closely match lichen-covered bark, whereas darker individuals more closely match plain bark”, said first author Olivia Walton, who conducted the research as part of her master’s degree at Exeter.

“Crucially, this translates into a strong survival advantage; the lighter moths are much less likely to be seen by wild birds when on lichen-covered backgrounds, in comparison to dark moths.”

In the experiment using artificial moths, lighter models had a 21% higher chance of “surviving” (not being eaten by birds).

“We provide strong direct evidence that the frequency of the peppered moth forms stems from differences in camouflage and avian predation, providing key support for this iconic example of natural selection,” Professor Stevens said.

The research was funded by the Biotechnology and Biological Sciences Research Council (BBSRC).

The paper, published in the journal Communications Biology, is entitled: “Avian vision models and field experiments determine the survival value of peppered moth camouflage.”

The birds that most commonly eat peppered moths include sparrows, great tits, blue tits, robins and blackbirds.

Young spoonbills and butterflies


This 23 April 2014 video is about the Polders Poelgeest nature reserve.

On 12 August 2018, to the Polders Poelgeest nature reserve.

Near the entrance, three gadwall ducks swimming.

In both the northern and southern lakes there are spoonbills. Both adults and juveniles, preparing to travel all the way to Africa.

Northern lapwings. Great cormorants on a small island.

Barn swallows flying overhead. A grey heron.

A female tufted duck with three ducklings in the northern lake.

Teal at their usual northern lake spot, not far from the railway.

Shoveler ducks.

In the new, far northern, part of the reserve: a barnacle goose and Canada geese.

Then, a special animal: a comma butterfly on a fence.

This is a comma butterfly video from England.

Finally, a smaller relative: a small heath butterfly.

This is a June 2016 small heath video from England.

Panama bryozoan evolution, new study


This video fom the USA says about itself:

9 October 2015

What are Fossil Bryozoans?

From the Smithsonian Tropical Research Institute in Panama:

Old species learn new tricks…very slowly

August 15, 2018

A quick look at the fossil record shows that no species lasts forever. On average, most species exist for around a million years, although some species persist for much longer. A new study published in Scientific Reports from paleontologists at the Smithsonian Tropical Research Institute in Panama shows that young species can take advantage of new opportunities more easily than older species: a hint that perhaps older species are bound to an established way of life.

“We’re lucky to live and work in Panama where nature has set up its own evolutionary experiment”, said Aaron O’Dea, STRI paleontologist. “When the Caribbean Sea was isolated from the Pacific Ocean by the slow uplift of the Isthmus of Panama, nutrient levels fell and Caribbean coral reefs proliferated. We can use the excellent fossil record to observe how Caribbean life responded to this dramatic environmental and ecological transformation.”

The team’s best choice for tracking the change was a peculiar family of marine animals known as the cupuladriid bryozoans. These relatively small animals consist of unusual, free-living, disc-shaped colonies of individuals called zooids. “Colonies form through sexual reproduction or asexually by cloning, as bits of the colony break off and continue to grow”, said STRI post-doc and coauthor Blanca Figuerola. “They abound on the sea floor along the continental shelf across the tropics, filtering plankton from the water via a beautiful waving crown of tentacles. When colonies die, their hard skeletons remain, and are exceptionally abundant as fossils.”

O’Dea’s group collected and identified more than 90,000 cupuladriid colonies from 200 fossil samples and 90 more recent samples collected by dredging the sea floor. The samples contained mud, sand, coral remains and other indicators of the kind of habitats where the bryozoans had lived. The team measured the abundances of the 10 most common species along gradients of these environmental and ecological indicators.

“We were intrigued to find that, even though all species could expand into the new Caribbean habitats created after final formation of the Isthmus, different species did so at different speeds”, said O’Dea. “The patterns were clear — old species that originated before 8 million years ago took 2 million years longer to expand into the new habitats than the younger species.”

“Perhaps younger species, which have smaller populations, are less tied to their history”, said former STRI post-doc and University of Saskatchewan researcher Santosh Jagadeeshan, another co-author. “Old species, with large, settled populations may be less able to escape from established roles and defined environmental tolerances because they mate with each other creating a high gene flow that makes it hard for genes for new traits to become established. It seems you can’t teach an old dog new tricks in evolution, either.”