North American stick insects´ colours, new research


This 2015 video from the USA says about itself

Walking Stick- Genus Timema mating

Filmed in Rainbow, California.

From Utah State University in the USA:

Genome-mapping reveals ‘supermutation’ resulting in cryptic coloration in stick insects

Summary: Biologists discuss findings from an investigation of genetic mutations in seven species of North American stick insects (Timema) resulting in cryptic coloration.

Traits that form an organism’s appearance, including color, are determined by many different genes and the creature’s environment.

“Humans and domestic animals, for example, have varied skin, fur and hair, as well as a range of heights — an example of continuous variation,” says Utah State University genetic ecologist Zach Gompert. “In the wild, however, types of genetic mutations affecting adaptation and thus, appearance, are only beginning to be understood. Some traits show more discontinuous or discrete variation.”

In a paper published July 23, 2020 in Science, Gompert and colleagues from the University of Sheffield, United Kingdom; France’s Paul Valéry University of Montpellier; the University of Bern and the Swiss Federal Institute for Aquatic Science and Technology, Switzerland; México’s Campus Juriquilla of the Autonomous University of Querétaro, University of Notre Dame and the University of Nevada-Reno, discuss findings from an investigation of seven species of North American stick insects (Timema).

“Most research on the genetic basis of traits and adaptation has focused on individual genes and small mutations,” says Gompert, associate professor in USU’s Department of Biology and the USU Ecology Center “But in this paper, we uncover a greater role for large mutations and structural rearrangements of the genome that effectively ‘lock up’ suites of genes in groups.”

The stick insects used in the study are flightless and plant-feeding. Most Timema species have green and brown-color “morphs,” a local variety of a species, which are cryptic, meaning they visually blend into their surroundings. Cryptic coloration enables the insects to avoid predation by birds, as they blend in on the leaves and stems or bark of the plants they eat. However, one species, Timema chumash, exhibits a range of morph colors, including greens and browns, but also yellow, orange, red, and shades of blue.

“Using genome-mapping methods, we show that a large, million base pair, adaptive deletion — a supermutation — converts a continuum of color variation seen in T. chumash into discrete color morphs in the other stick insect species,” Gompert says. “This finding is important, as it helps reconcile large evolutionary shifts or gaps with the continuous process of evolution. It also provides insights into how continuous variation is packaged into semi-discrete units of biological diversity, such as morphs, sexes and species.”

Colourful dinosaur age insects discovered


Diverse structural-colored insects in mid-Cretaceous amber from northern Myanmar. Credit: NIGPAS

From the Chinese Academy of Sciences, 30 June 2020:

Amber fossils unlock true color of 99-million-year-old insects

Nature is full of colors, from the radiant shine of a peacock‘s feathers or the bright warning coloration of toxic frogs to the pearl-white camouflage of polar bears.

Usually, fine structural detail necessary for the conservation of color is rarely preserved in the , making most reconstructions of the dependent upon an artist’s imagination.

A research team from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) has now unlocked the secrets of true coloration in 99-million-year-old insects.

Colors offer many clues about the behavior and ecology of animals. They function to keep organisms safe from predators, at the right temperature, or attractive to potential mates. Understanding the coloration of long-extinct animals can help us shed light on ecosystems in the deep geological past.

The study, published in Proceedings of the Royal Society B on July 1, offers a new perspective on the often overlooked, but by no means dull, lives of insects that co-existed alongside dinosaurs in Cretaceous rainforests.

Researchers gathered a treasure trove of 35 amber pieces with exquisitely preserved insects from an amber mine in northern Myanmar.

“The amber is mid-Cretaceous, approximately 99 million years old, dating back to the golden age of dinosaurs. It is essentially resin produced by ancient coniferous trees that grew in a tropical rainforest environment. Animals and plants trapped in the thick resin got preserved, some with life-like fidelity,” said Dr. Cai Chenyang, associate professor at NIGPAS who lead the study.

The rare set of amber fossils includes cuckoo wasps with metallic bluish-green, yellowish-green, purplish-blue or green on the head, thorax, abdomen, and legs. In terms of color, they are almost the same as cuckoo wasps that live today, said Dr. Cai.

The researchers also discovered blue and purple beetle specimens and a metallic dark-green soldier fly. “We have seen thousands of amber fossils but the preservation of color in these specimens is extraordinary,” said Prof. Huang Diying from NIGPAS, a co-author of the study.

“The type of color preserved in the amber fossils is called structural color. It is caused by microscopic structure of the animal’s surface. The surface nanostructure scatters light of specific wavelengths and produces very intense colors. This mechanism is responsible for many of the colors we know from our everyday lives,” explained Prof. Pan Yanhong from NIGPAS, a specialist on palaeocolor reconstruction.

To understand how and why color is preserved in some amber fossils but not in others, and whether the colors seen in fossils are the same as the ones insects paraded more than 99 million years ago, the researchers used diamond knife blades to cut through the exoskeleton of two of the colorful amber wasps and a sample of normal dull cuticle.

Using , they were able to show that colorful amber fossils have a well-preserved exoskeleton nanostructure that scatters light. The unaltered nanostructure of colored insects suggested that the colors preserved in amber may be the same as the ones displayed by them in the Cretaceous. But in fossils that do not preserve color, the cuticular structures are badly damaged, explaining their brown-black appearance.

What kind of information can we learn about the lives of ancient insects from their color?

Extant cuckoo wasps are, as their name suggests, parasites that lay their eggs into the nests of unrelated bees and wasps. Structural coloration has been shown to serve as camouflage in insects, and so it is probable that the color of Cretaceous cuckoo wasps represented an adaptation to avoid detection. “At the moment we also cannot rule out the possibility that the colors played other roles besides camouflage, such as thermoregulation,” adds Dr. Cai.

Salmon flies in the USA, video


This 24 June 2020 video from Yellowstone Park in the USA says about itself:

A Bug Undergoes One of Nature’s More Startling Transformations

The salmon fly nymph is in a race against time: in order to breathe, it will need to break out of its hardened exoskeleton and complete a fascinating metamorphosis.

Hummingbirds, praying mantis, bees at Texas feeder


This video from the USA says about itself:

Praying Mantis Visits Hummingbird Feeder In West Texas – June 25, 2020

A praying mantis drops down to the hummingbird feeders and scuttles from port to port, likely in search of an insect [bee] meal. In rare cases, larger mantids have been documented staking out hummingbird feeders and preying on the birds that visit, but this individual is too small to be a risk to the birds.

Old bugs, young bugs, different colours


This May 2019 video says about itself:

The green shield bug – Palomena prasina – is a European shield bug species in the family Pentatomidae. The name might equally apply to several other species in the tribe Nezarini, or if referred-to as a “green stink bug”, it might more appropriately belong to the larger North American bug, Acrosternum hilare.

From the University of Melbourne in Australia:

Bugs resort to several colors to protect themselves from predators

Colorful bugs look very different as young and adults, but why?

June 25, 2020

Summary: New research has revealed for the first time that shield bugs use a variety of colors throughout their lives to avoid predators. For years it has been thought that animals living in the same environment — like nymphs and adults of the same species — should use similar warning colors, not different ones.

New research has revealed for the first time that shield bugs use a variety of colours throughout their lives to avoid predators.

Shield bugs are often bright, colourful insects that use colours to warn off their distastefulness to predators. The paper, published in Proceedings of the Royal Society B, found that it is impossible to predict how an adult bug will look like based on their colour when young.

“We found that in most species, the same individual bug will use different colour combinations as nymphs — young bugs — and adults, going for example from red and green to yellow and green,” said lead author and ecologist, Dr Iliana Medina, from the University of Melbourne’s School of Biosciences.

“This is significant because many of these species use colour to warn predators that they are distasteful, and for years it has been thought that animals living in the same environment — like nymphs and adults of the same species — should use similar warning colours, not different ones.”

The joint research between scientists at the University of Melbourne and the Australian National University combined information on colour in young and adults for more than 100 species of shield bugs worldwide. They then used fieldwork in Canberra, with white-winged choughs, to measure how likely these birds were to attack adult and nymphs of one Australian species of shield bug, the cotton harlequin bug.

Experiments were also conducted in the aviary, training two-week-old chicks to see how fast they learned to avoid nymphs and adults, then testing whether their previous experience with adults could reduce attack rates on nymphs.

“Our experiments with the cotton harlequin bug showed that predators could quickly learn to avoid both types of colour signals from nymphs and adults, but nymphs get a larger benefit,” Dr Medina said.

“Although young and adult cotton harlequin bugs have different colours, previous experience with adults make chicks less likely to attack the nymphs. Also, chicks and wild predators that have never seen the insects before do not show much interest in eating them. The colours in these insects are a great strategy against predators.”

Many animals such as frogs, insects and sea slugs use bright colourations to advertise toxicity or distastefulness. In theory, warning signals of prey that live in the same environment should be the same because predators can learn more effectively to avoid one type of pattern, instead of many different ones.

While this idea has been used to explain the great examples of mimicry in nature, and why distantly related species end up having the same warning colours, such as black and red, or black and yellow, researchers say there are multiple examples of variation in local warning signals and an overlooked type of variation is that across life stages.

“If predators were able to learn to avoid only one type of warning colour, we would expect nymphs and adults to look similar in many species,” Dr Medina said. “What our findings show, however, is that the wide colour variation in shield bugs is probably the result of predators being able to learn to avoid different types of colourful signals.”

French stick insects discovered in the Netherlands


This video from Portugal says about itself:

Atlantic Species | French stick insect Clonopsis gallica

Micro-Documentaries on marine and land species of the Atlantic region produced by the AtlanticNaturalist.org in partnership with Nature tour company http://www.Naturalist.pt!

French stick insect, Bicho-pau, Gallische Mittelmeerstabschrecke, bicho palo, Phasme gaulois.

Clonopsis gallica is a stick insect, a species known for their capacity to mimic leaves and wood branches. It belongs to the Phasmida, a group of leaf and stick insects. With over 2000 species spread around the world, particularly in tropical and sub-tropical regions.

Genus are normally easily distinguished by their overall shape, the shape of head and size of antennae, however, to separate some species it may be necessary to do electron microscopy.

Clonopsis gallica is an obligate parthenogen, producing eggs and offspring without requiring fertilization. It has three stages, the egg, the nymph and the adult, and you may find them in green or in more brownish colour. This species is common in Southern Europe, from France to the Mediterranean coast, North-Western Africa, including Azores and Madeira. These are herbivore insects, presenting no threats to crops, and you can find it active during night periods, and camouflaged during the day.

In 2019, this species has been discovered in the Netherlands; the first time for any stick insect species.