Birds and insects of Voorne island, video


This 7 May 2020 video shows birds and insects of Voorne island in the Netherlands. Sequence: kestrel, goldfinch, sedge warbler, northern shoveler duck, redshanks, northern lapwing with chick, robin, wren, whitethroat, brimstone butterfly, common scorpionfly, green-veined white butterfly, hoverfly, peacock butterfly and firebug.

How treefrogs fool predators


This video says about itself:

Cross-Banded Treefrog Call

Impolite Science Nature: 2009 Trek to Panama. Duration: 0:50. The Cross-Banded Treefrog (Smilisca sila) was found in Santa Catalina on the banks of a small stream. This frog has more complex calls with a full moon and may be able to detect predatory bats.

Many frogs, including this one here, do not seem to be disturbed by red light, although it seems that frogs do see color at night very well.

From Purdue University in the USA:

Outsmarting the enemy: [Panama cross-banded] Treefrogs rely on illusions to find a mate without being eaten

May 6, 2020

Summary: Researchers have discovered that male treefrogs reduce their attractiveness to predators and parasites by overlapping their mating calls with their neighbors.

Treefrogs become easy targets for predators and parasites when they send mating calls, but they’re finding a way to fool their enemies with a little help from a wingman.

Researchers at Purdue University have discovered that male treefrogs reduce their attractiveness to predators and parasites by overlapping their mating calls with their neighbors. By overlapping their calls at nearly perfect synchrony with neighboring treefrogs, an auditory illusion takes effect and those enemies are more attracted to the leading call, leaving the other frogs to find mates without risking their life. The work was recently published in American Naturalist.

“The male frogs are essentially manipulating the eavesdroppers through creating this auditory illusion,” said doctoral student Henry Legett, who led the research with Ximena Bernal, associate professor of biological sciences at Purdue University. “Humans experience this illusion too, it’s called the ‘Precedence Effect.’ When we hear two short sounds in quick succession, we think the sound is only coming from the location of the first sound.”

Research at the Bernal lab focuses on the relationship between predation and communication — or what they simply refer to as eavesdropping.

“The illusion created by the male treefrogs calling in synchrony has no effect on female frogs, which was a surprising observation,” Bernal says.

“These male frogs have figured out a way to trick these enemies. We thought the females might be more attracted to the leading caller, but it didn’t really affect attraction at all. It’s a win-win for the frogs because it helps reduce attacks from those enemies who were hoping to prey on the male frogs and females are not tricked by the illusion.”

The study included experiments using playbacks of recorded calls from speakers and sound traps both in laboratory and field settings at the Smithsonian Tropical Research Institute in Panama, where Bernal is a research associate and frequently visits to work with students. Researchers discovered that after the initial male treefrog sends a mating call, other frogs follow suit within milliseconds.

“It’s so fast, it’s almost like a reflex,” Legett said. “There’s no way their brains have time to process that information. They hear their neighbor and they react immediately.”

Bernal and Legett said the research has cultivated even more questions about how frogs communicate.

“You have to wonder why a male frog would call first, given that if increases his chances of being eaten,” Legett said. “It’s a very strategic game they’re playing. The frog that calls first might not get lucky that time, but maybe he knows he’ll get his chance the next time he hears one of his friends make the first call. These are the questions we’ll keep asking as we move forward.”

Brittle stars see with their skin


This 6 May 2020 video says about itself:

Brittle Stars Could Teach Robots To See With Their Skin

Brittle stars are eyeless, brainless animals that spend their time hanging out in dark crevices of coral reefs. But despite all this, it seems that they can still see…using their skin!

Hosted by: Hank Green.