Dewdrops on damselfly, video

This 5 September 2019 video shows a damselfly trying to get dewdrops off its head and legs early in the morning.

Ronald van Dijk in the Netherlands made this video.


Wasps’ social life, video

This 3 September 2019 video says about itself:

These Wasps Throw Awesome Parties

Large clumps of wasps can occasionally be found on the tops of tall structures, and although you probably still don’t want to mess with them, these aren’t angry swarms—they’re actually super chill parties.

Hosted by: Olivia Gordon

Sphingonotus caerulans grasshopper video

This 25 August 2019 video by Roy Kleukers in the Netherlands shows a Sphingonotus caerulans grasshopper.

This is originally a south European species.

According to Wikipedia, its ‘northern limit is northern France’.

However, recently more and more of these animals are seen in Belgium and the Netherlands.

Good beewolf news from Texel island

This August 2017 video says about itself:

A short story on the European Beewolf wasp (Philanthus triangulum) showing how it preys on others and what it does to improve the success of its offspring. Shot on heathland.

Wildlife warden Huib Koel reports today from Texel island in the Netherlands:

The beewolves on Texel are doing well

The tourists are not the only ones who enjoy the summer temperatures on Texel, also the solitary beewolves – a species of wasp that is not dangerous to humans – benefit from the heat. The bird watchers at De Slufter discovered more than a hundred nests at the end of last month alongside the bike path at the Zanddijk dunes. Last year the counter stopped at around thirty heaps of sand made by the beewolves. Beewolves catch honey bees as food for their young.

At De Slufter, the beewolves do not have to fly far, because every year a beekeeper puts his hives with tens of thousands of honey bees very close to the nest location of the beewolves. His honey bees get nectar from the flowering sea lavender in De Slufter, but several hundred honey bees end their lives in the wolves’ nest. …

Rare species discovered

This year the bird watchers discovered another insect that keeps a close eye on the activities of the bee wolves. An insect with fantastic green and red shiny, metallic colours. It is one of the most beautiful insects in the Netherlands: an emerald wasp with the scientific name Hedychrum rutilans of less than a centimeter in size. It is a rare wasp species, although it has been observed more frequently in recent years – just like the beewolves. It is the only emerald wasp that targets beewolves. Other jewel wasps have other victims. … She tries to deposit her egg in the beewolf’s nest. According to the EIS research agency of Naturalis, this is the seventh observation of this jewel wasp on Texel.

Hedychrum rutilans

Eocene fossil crane-flies’ eyes, new research

This 15 August 2019 video says about itself:

Exceptionally Detailed Fossil [Crane-]Fly Eyes Discovered In Denmark

The ancient eyes, each just 1.25mm across, belonged to a tiny crane-fly that lived 54 million years ago. Discovered by Lund University researchers, evidence of pigment within them is shedding new light on the evolution of compound eyes.

From Lund University in Sweden:

Composition of fossil insect eyes surprises researchers

August 15, 2019

Eumelanin — a natural pigment found for instance in human eyes — has, for the first time, been identified in the fossilized compound eyes of 54-million-year-old crane-flies. It was previously assumed that melanic screening pigments did not exist in arthropods.

“We were surprised by what we found because we were not looking for, or expecting it,” says Johan Lindgren, an Associate Professor at the Department of Geology, Lund University, and lead author of the study published this week in the journal Nature.

The researchers went on to examine the eyes of living crane-flies, and found additional evidence for eumelanin in the modern species as well.

By comparing the fossilized eyes with optic tissues from living crane-flies, the researchers were able to look closer at how the fossilization process has affected the conservation of compound eyes across geological time.

The fossilized eyes further possessed calcified ommatidial lenses, and Johan Lindgren believes that this mineral has replaced the original chitinous material.

This, in turn, led the researchers to conclude that another widely held hypothesis may need to be reconsidered. Previous research has suggested that trilobites — an exceedingly well-known group of extinct seagoing arthropods — had mineralized lenses in life.

“The general view has been that trilobites had lenses made from single calcium carbonate crystals. However, they were probably much more similar to modern arthropods in that their eyes were primarily organic,” says Johan Lindgren.

Compound eyes are found in arthropods, such as insects and crustaceans, and are the most common visual organ seen in the animal kingdom. They are made up of multiple tiny and light-sensitive ommatidia, and the perceived image is a combination of inputs from these individual units.