Introduction

	The most recent understanding of the evolution of insects is based on studies of the following branches of science: molecular biology, insect morphology, paleontology, insect taxonomy, evolution, embryology, bioinformatics and scientific computing. It is estimated that the class of insects originated on Earth about 480 million years ago, in the Ordovician, at about the same time terrestrial plants appeared Insects are thought to have evolved from a group of crustaceans. The first insects were landbound, but about 400 million years ago in the Devonian period one lineage of insects evolved flight, the first animals to do so. The oldest insect fossil has been proposed to be Rhyniognatha hirsti, estimated to be 400 million years old, but the insect identity of the fossil has been contested. Global climate conditions changed several times during the history of Earth, and along with it the diversity of insects. The Pterygotes (winged insects) underwent a major radiation in the Carboniferous (356 to 299 million years ago) while the Endopterygota (insects that go through different life stages with metamorphosis) underwent another major radiation in the Permian (299 to 252 million years ago).	Most extant orders of insects developed during the Permian period. Many of the early groups became extinct during the mass extinction at the Permo-Triassic boundary, the largest extinction event in the history of the Earth, around 252 million years ago. The survivors of this event evolved in the Triassic (252 to 201 million years ago) to what are essentially the modern insect orders that persist to this day. Most modern insect families appeared in the Jurassic (201 to 145 million years ago).	In an important example of co-evolution, a number of highly successful insect groups — especially the Hymenoptera (wasps, bees and ants) and Lepidoptera (butterflies) as well as many types of Diptera (flies) and Coleoptera (beetles) — evolved in conjunction with flowering plants during the Cretaceous (145 to 66 million years ago). 	Many modern insect genera developed during the Cenozoic that began about 66 million years ago; insects from this period onwards frequently became preserved in amber, often in perfect condition. Such specimens are easily compared with modern species, and most of them are members of extant genera.

© https://en.wikipedia.org/wiki/Evolution_of_insects

EVOLUTION:  https://en.wikipedia.org/wiki/Evolution_of_insectsEVOLUTION (British Natural History Museum): https://www.nhm.ac.uk/discover/news/2014/november/intricacies-insect-evolution-revealed.htmlEVOLUTION (Stanford University): https://earth.stanford.edu/news/insects-took-when-they-evolved-wingsEVOLUTION (Cornell University VIDEO): https://www.cornell.edu/video/insect-evolution

Arthropods

•	Arthropods are the largest phylum in the animal kingdom, which includes such familiar forms as lobsters, crabs, spiders, mites, insects, centipedes, and millipedes. •	About 84 percent of all known species of animals are members of this phylum. •	Arthropods are represented in every habitat on Earth and show a great variety of adaptations. Several types live in aquatic environments, and others reside in terrestrial ones; some groups are even adapted for flight.•	The distinguishing feature of arthropods is the presence of a jointed skeletal covering composed of chitin (a complex sugar) bound to protein. This nonliving exoskeleton is secreted by the underlying epidermis (which corresponds to the skin of other animals). •	The body of arthropods is usually segmented, and the segments bear paired jointed appendages, from which the name arthropod (“jointed feet”) is derived. •	About one million arthropod species have been described, of which most are insects. •	This number, however, may be only a fraction of the total. •	Based on the number of undescribed species collected from the treetops of tropical forests, zoologists have estimated the total number of insect species alone to be as high as 5.5 million. The more than 48,000 described species of mites may also represent only a fraction of the existing number.•	The phylum Arthropoda is commonly divided into four subphyla of extant forms:  	1. Arachnids (i.e. spiders and scorpions) 	2. Crustaceans(i.e. lobsters and shrimp), 	3. Insects and springtails	4. millipedes and centipedes.

OVERVIEW: https://manoa.hawaii.edu/exploringourfluidearth/biological/invertebrates/phylum-arthropoda OVERVIEW (Smithsonian Video): https://www.youtube.com/watch?v=puKoq5fzyAg 

What is an insect?

	Insects are animals that have roamed the earth for at least 300 million years, so they have been around way before dinosaurs.   Dinosaurs are extinct, but insects are still with us and some have changed very little since the days of the dinosaurs.    	With over 1,000,000 different kinds, insects have the honor of being the most numerous of all life forms on earth, and if you go out looking for them, they can be found almost everywhere on planet earth, even in the Artic.   Most live on land, but some live in fresh water, and a few can be found living in the oceans.  On land insects can be found high up on trees, or active deep in the soil, flying day and night, or crawling on the ground.    	All insects have three body parts: a head, a thorax, and an abdomen.  They also have three pairs of jointed legs (six legs in total), a pair of antennae, and zero, one, or two pairs of wings.  Insects are the only arthropods that can fly.	There are reasons why insects have been around so long and why there are so many different kinds.   Insects owe much of their success to the following: •	Most insects have wings.   Wings have helped insects move around.   So when food becomes hard to find in one area, they can fly to another place with food.•	Adaptations.   There a many ways that insects have changed their behavior or body in some way to live indifferent habitats and feed on different plants or animals.   These changes include different kinds of legs, antennae, and mouthparts.  •	Eat about anything.   Insects will feed many things that we would expect them to, like plants in our gardens.   But some will feed on things that we would think are inedible, such as wood.   Some insects feed on a lot of different things, such as plants, while other may only eat a certain type of plant.•	Large reproductive capacity.   Most insects can have a lot of babies.   This helps adaptations to occur and increases survival.    There are some termite queens that can lay 30,000 eggs per day, and the queens may live for 10 years.

© https://entomology.unl.edu/scilit/what-insect© https://naturalhistory.si.edu/education/teaching-resources/life-science/what-insect

OVERVIEW:  (Smithsonian): https://www.youtube.com/watch?v=kdC7FHxi-LgOVERVIEW: https://www.youtube.com/watch?v=YjOFjzLgY0M OVERVIEW:  https://www.youtube.com/watch?v=kO-xGZsq0_w

	Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of 22,000 species have been classified. They are easily identified by their geniculate (elbowed) antennae and the distinctive node-like structure that forms their slender waists.	Ants form colonies that range in size from a few dozen predatory individuals living in small natural cavities to highly organized colonies that may occupy large territories and consist of millions of individuals. Larger colonies consist of various castes of sterile, wingless females, most of which are workers (ergates), as well as soldiers (dinergates) and other specialized groups. Nearly all ant colonies also have some fertile males called "drones" and one or more fertile females called "queens" (gynes). The colonies are described as superorganisms because the ants appear to operate as a unified entity, collectively working together to support the colony.	Ants have colonized almost every landmass on Earth. The only places lacking indigenous ants are Antarctica and a few remote or inhospitable islands. Ants thrive in moist tropical ecosystems and may exceed the combined biomass of wild birds and mammals. Their success in so many environments has been attributed to their social organization and their ability to modify habitats, tap resources, and defend themselves. Their long co-evolution with other species has led to mimetic, commensal, parasitic, and mutualistic relationships.	Ant societies have division of labor, communication between individuals, and an ability to solve complex problems. These parallels with human societies have long been an inspiration and subject of study. Many human cultures make use of ants in cuisine, medication, and rites. Some species are valued in their role as biological pest control agents. Their ability to exploit resources may bring ants into conflict with humans, however, as they can damage crops and invade buildings. Some species, such as the red imported fire ant (Solenopsis invicta) of South America, are regarded as invasive species in other parts of the world, establishing themselves in areas where they have been introduced accidentally.© https://en.wikipedia.org/wiki/Ant
ANT HILLS (video):  https://www.youtube.com/watch?v=HedZXw_hAbsEVOLUTION OF ANTS (video): https://www.youtube.com/watch?v=_qi8bcTONrMOVERVIEW: https://www.nationalgeographic.com/animals/invertebrates/facts/ants?OVERVIEW: https://extension.umn.edu/insects-infest-homes/antsOVERVIEW: https://en.wikipedia.org/wiki/Ant

Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are presently considered a clade, called Anthophila. There are over 16,000 known species of bees in seven recognized biological families. Some species – including honey bees, bumblebees, and stingless bees – live socially in colonies while most species (>90%) – including mason bees, carpenter bees, leafcutter bees, and sweat bees – are solitary.		Bees are found on every continent except Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants. The most common bees in the Northern Hemisphere are the Halictidae, or sweat bees, but they are small and often mistaken for wasps or flies. Bees range in size from tiny stingless bee species, whose workers are less than 2 millimeters (0.08 in) long, to Megachile pluto, the largest species of leafcutter bee, whose females can attain a length of 39 millimeters (1.54 in).	Bees feed on nectar and pollen, the former primarily as an energy source and the latter primarily for protein and other nutrients. Most pollen is used as food for their larvae. Vertebrate predators of bees include primates and birds such as bee-eaters; insect predators include beewolves and dragonflies.	Bee pollination is important both ecologically and commercially, and the decline in wild bees has increased the value of pollination by commercially managed hives of honey bees. The analysis of 353 wild bee and hoverfly species across Britain from 1980 to 2013 found the insects have been lost from a quarter of the places they inhabited in 1980.	Human beekeeping or apiculture (meliponiculture for stingless bees) has been practiced for millennia, since at least the times of Ancient Egypt and Ancient Greece. Bees have appeared in mythology and folklore, through all phases of art and literature from ancient times to the present day, although primarily focused in the Northern Hemisphere where beekeeping is far more common. In Mesoamerica, the Mayans have practiced large-scale intensive meliponiculture since pre-Columbian times.© https://en.wikipedia.org/wiki/Bee
EVOLUTION OF BEES (video):  https://www.youtube.com/watch?v=Wyc6ZnfEN-IBEES (Jobs in Nest; video): https://www.youtube.com/watch?v=9ePic3dtykkOVERVIEW:  https://en.wikipedia.org/wiki/BeeOVERVIEW: https://www.britannica.com/animal/beeTOP TEN FACTS (Kid friendly): https://www.wwf.org.uk/learn/fascinating-facts/bees

        Butterflies (Rhopalocera) are insects that have large, often brightly coloured wings, and a conspicuous, fluttering flight. The group comprises the superfamilies Hedyloidea (moth-butterflies in the Americas) and Papilionoidea. Butterfly fossils date to the Paleocene, about 56 million years ago.	Butterflies have a four-stage life cycle, as like most insects they undergo complete metamorphosis. Winged adults lay eggs on the food plant on which their larvae, known as caterpillars, will feed. The caterpillars grow, sometimes very rapidly, and when fully developed, pupate in a chrysalis. When metamorphosis is complete, the pupal skin splits, the adult insect climbs out, and after its wings have expanded and dried, it flies off. Some butterflies, especially in the tropics, have several generations in a year, while others have a single generation, and a few in cold locations may take several years to pass through their entire life cycle.	Butterflies are often polymorphic, and many species make use of camouflage, mimicry, and aposematism to evade their predators. Some, like the monarch and the painted lady, migrate over long distances. Many butterflies are attacked by parasites or parasitoids, including wasps, protozoans, flies, and other invertebrates, or are preyed upon by other organisms. Some species are pests because in their larval stages they can damage domestic crops or trees; other species are agents of pollination of some plants. Larvae of a few butterflies (e.g., harvesters) eat harmful insects, and a few are predators of ants, while others live as mutualists in association with ants. Culturally, butterflies are a popular motif in the visual and literary arts. The Smithsonian Institution says "butterflies are certainly one of the most appealing creatures in nature.”© https://en.wikipedia.org/wiki/Butterfly
OVERVIEW:  https://www.si.edu/spotlight/buginfo/butterflyOVERVIEW: https://en.wikipedia.org/wiki/ButterflyEVOLUTION OF BUTTERFLIES (video): https://www.youtube.com/watch?v=CmbuBbd1wTMMONARCH BUTTERFLY SWARM (Video): https://www.youtube.com/watch?v=lWOySU_hAz0

       Moths are in the insect Order Lepidoptera and share this Order with Butterflies. There are some 160,000 species of moths in the world, compared to 17,500 species of butterflies. In the United States, there are nearly 11,000 species of moths.	Moths (and their close relatives, the butterflies) are the only group of insects that have scales covering their wings, although there are a few exceptions. They differ from other insects also by their ability to coil up their feeding tube (the proboscis). Moths can usually be distinguished from butterflies by their antennae, which are typically threadlike or feathery; in contrast, butterflies have club-tipped antennae.	Although moths have for the most part relatively dull wing colors, there are many species with spectacular colors and patterns. The Giant Silkworm Moths form a vast array of large, impressive insects with colorful wings, sometimes with long tails on the hind wings. One of the moth species most commonly seen is the Tomato Hornworm Moth, although it is noticed in the caterpillar stage as it devours tomato foliage in the garden. Opposite to the habits of butterflies, moths usually fly during the night to gather nectar at flowers. However, there are many day-flying moths, and many of them are brightly colored. The insect that is often considered as the most beautiful insect in the world is a day-flying moth, The Sunset Moth, from Madagascar. Day-flying moths are often noticed feeding at flowers.	Caterpillars are the name given to the larvae of both moths and butterflies. They are usually very distinctive, and in some cases may be identified more easily than the adults. Caterpillars eat voraciously to transform plant material into the tissues that they will need for changing into moths.	Migration in the Lepidoptera is not limited to butterflies such as the Monarch. There are many migratory moths, including the day flying Hummingbird Hawkmoth, which migrates from southern parts to northern parts of Europe as temperatures rise in early summer.	The Peppered Moth of Europe is commonly cited as a classic example in evolution, and was studied by H. B. D. Kettlewell as an example of "industrial melanism. Moths with salt and pepper colored wings are not detected on bark that contains lichens of similar colors and patterns. Trees during the industrial revolution became so soot-covered that moths with genetic makeup for dark colors developed because they were not seen and eaten by birds. The reverse of this mechanism has resulted through time as tree bark returned to a lighter color.	Moths are divided into many families that have different morphological characteristics. The following families include the majority of moth species:	Arctiidae. There are approximately 10,000 species of this Family in the world, and they are commonly called Tiger Moths. Many species in this group display bright colors of red and yellow.	Geometridae. With some 15,000 described species, this Family is the second largest of moths in the world. Larvae are usually called "inch-worms" because of their walking patterns.	Noctuidae. This Family is by far the largest in moths, with some 25,000 known species in the world. Cutworms, fruitworms and underwing moths occur in this Family.	Saturniidae. This Family includes the largest of moths, and incorporates some 1,000 worldwide species. The Luna Moth of the Eastern United States is an example of this Family.	Sphingidae. Members of this Family have streamlined wings and robust bodies. They are generally large, and the Family contains about 1,000 species.	Microlepidoptera is the term given to a wide variety of very small moths (with few exceptions). The group contains many thousands of tiny species, some with spectacular colors and appearances. Some are pest species, such as the Clothes Moth and the Codling Moth.	© Prepared by the Department of Systematic Biology, Entomology Section,National Museum of Natural History, in cooperation with Public Inquiry Services,  Smithsonian Institution	
OVERVIEW: https://www.britannica.com/animal/moth-insectOVERVIEW: https://en.wikipedia.org/wiki/Moth MOTHS:  https://www.youtube.com/watch?v=YaI1zE3AOXoDIFFERENCE BETWEEN MOTHS AND BUTTERFLIES: https://www.youtube.com/watch?v=kMOpknqDO5s&t=159s  DIFFERENCE BETWEEN MOTHS AND BUTTERFLIES: https://www.youtube.com/watch?v=y2xFC55aEnY 

Not Insects

There are a great number of animals that people mistakenly lump together with insects. Like insects, they are arthropods, but they are immediately distinguished by their physiognomy.Here are three animals that are often mislabeled. 

CENTIPEDES AND MILLIPEDES	Both centipedes and millipedes are made up of segments that link together to form one, long body. With this body form in common, it might be hard to tell the difference between the two at first glance. Here are a few tips to spot the differences:	Millipedes have two sets of legs per segment positioned directly under their body. Centipedes have one set of legs per segment positioned on the side of their body.    	Centipedes mostly eat insects after killing them with their venom. Millipedes feast on decomposing plants.   	 If looking from the side, centipedes have a flatter body while millipedes are more rounded.    	They respond to threats in different ways. A millipede will coil up and release a smelly secretion. Centipedes can bite (which is typically harmless to humans) and run away quickly.    	Scientists have grouped them together because of their similar segmented bodies.  	  Both have poor or non-existent vision and rely on other senses, like the feel of vibrations.   	 They prefer to live in dark environments, which is why you may have seen them in an unlit corner of your basement.    	The longest species of each measure about six inches in length.	There are more than 3,000 known and an estimated 8,000 species of centipedes. There are upwards of 7,000 known and 80,000 estimated species of millipedes. Millipedes can be found in moist forest areas, while centipedes prefer dry environments. 		A final note:  “Milli” is a Latin prefix for 1,000 and “centi” is for 100.  Don’t assume that’s exactly how many legs each has on its entire body, though! Some species of millipedes can have as many as 750 legs. Centipedes can have more than 350 legs.© https://carnegiemnh.org/centipede-or-millipede-whats-the-difference/ 

SPIDERS	Spiders are air-breathing arthropods that have eight legs, possess fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species diversity among all orders of organisms. Spiders are found worldwide on every continent except for Antarctica and have become established in nearly every land habitat. As of August 2022, 50,356 spider species in 132 families have been recorded by taxonomists. 	Anatomically, spiders (as with all arachnids) differ from other arthropods in that the usual three body segments are fused into two.  Because there is currently neither paleontological nor embryological evidence that spiders ever had a separate thorax-like division, there exists an argument against the validity of the term cephalothorax, which means fused cephalon (head) and the thorax. 	Unlike insects, spiders do not have antennae. In all except the most primitive group, spiders have the most centralized nervous systems of all arthropods, as all their ganglia are fused into one mass in the cephalothorax. Unlike most arthropods, spiders have no extensor muscles in their limbs and instead extend them by hydraulic pressure.	Spiders' guts are too narrow to take solids, so they liquefy their food by flooding it with digestive enzymes. They also grind food with the bases of their pedipalps, as arachnids do not have the mandibles that crustaceans and insects have.	To avoid being eaten by the females, which are typically much larger, male spiders identify themselves to potential mates by a variety of complex courtship rituals. Males of most species survive a few matings but are limited mainly by their short life spans. Females weave silk egg-cases, each of which may contain hundreds of eggs. Females of many species care for their young, for example by carrying them around or by sharing food with them. A minority of species are social, building communal webs that may house anywhere from a few to 50,000 individuals. Social behavior ranges from precarious toleration, as in the widow spiders, to co-operative hunting and food-sharing. Although most spiders live for at most two years, tarantulas and other mygalomorph spiders can live up to 25 years in captivity.	While the venom of a few species is dangerous to humans, scientists are now researching the use of spider venom in medicine and as non-polluting pesticides. Spider silk provides a combination of lightness, strength and elasticity that is superior to that of synthetic materials, and spider silk genes have been inserted into mammals and plants to see if these can be used as silk factories. As a result of their wide range of behaviors, spiders have become common symbols in art and mythology symbolizing various combinations of patience, cruelty, and creative powers. 	An irrational fear of spiders is called arachnophobia.	© https://en.wikipedia.org/wiki/Spider  

SCORPIONS	Scorpions are predatory arachnids that have eight legs and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always ending with a stinger. The evolutionary history of scorpions goes back 435 million years. They mainly live in deserts but have adapted to a wide range of environmental conditions and can be found on all continents except Antarctica. There are over 2,500 described species, with 22 extant (living) families recognized to date. 	Scorpions primarily prey on insects and other invertebrates, but some species hunt vertebrates. They use their pincers to restrain and kill prey, or to prevent their own predation. The venomous sting is used for offense and defense. During courtship, the male and female grasp each other's pincers and dance while he tries to move her onto his sperm packet. All known species give live birth and the female cares for the young as their exoskeletons harden, transporting them on her back. The exoskeleton contains fluorescent chemicals and glows under ultraviolet light.	The vast majority of species do not seriously threaten humans, and healthy adults usually do not need medical treatment after a sting. About 25 species (fewer than one percent) have venom capable of killing a human, which happens frequently in the parts of the world where they live, primarily where access to medical treatment is unlikely.	Scorpions appear in art, folklore, mythology, and commercial brands. Scorpion motifs are woven into kilim carpets for protection from their sting. Scorpius is the name of a constellation; the corresponding astrological sign is Scorpio. A classical myth about Scorpius tells how the giant scorpion and its enemy Orion became constellations on opposite sides of the sky.© https://en.wikipedia.org/wiki/Scorpion 

What's the Buzz? The Fantastic World of Insects

Introduction

American Museum of Natural History

Recommended Media

Arthropods

What is an insect?

Ants

Bees

Butterflies

Moths

Significant Others

Not Insects