Day 13 Hexapoda
NGSS Standard: Molecules for Organisms HS-LS1-2
Students who demonstrate understanding can:
HS-LS1-2.
Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms. [Clarification Statement: Emphasis is on functions at the organism system level such as nutrient uptake, water delivery, and organism movement in response to neural stimuli. An example of an interacting system could be an artery depending on the proper function of elastic tissue and smooth muscle to regulate and deliver the proper amount of blood within the circulatory system.] [Assessment Boundary: Assessment does not include interactions and functions at the molecular or chemical reaction level.]
Student Assessment:
Individual Activity:
Open your sketchbook and I want you to write the word "Bug". Spend a minute thinking about this word. Now I want you to write down your definition of the word "Bug".
Now share your definitions with the class.
Class Activity:
On the lab tables you will find jars, cages, and containers. In these enclosures are living specimens from the phyla Arthropoda. Today we are learning about insects but not all of these organisms are insects. You are to go to the tables with your sketchbook and observe the animals.
There are more species of Arthropods in the world than any other type of animal. Classifying Arthropods or taxonomy of Arthropods can be tricky. How would you classify them...or name them?
All the enclosures are numbered. I want you to describe the organisms within the containers and I want you to tell me how you would group them. For example would you group all the animals with wings together? How about group them by body parts? How many legs? Maybe they should all be in their own groups. You have 15 minutes to make your observations. Then we will sit down and share our findings.
Subphylum Hexapoda (Six Legs)
Class Insecta
(Latin Insectum coming from the Greek Entomon - Cut into segments) (Entomologists study insects)
Insect Characteristics
-Mandibles - Mouth appendages exposed and projected from head
-Exoskeleton made of Chitin
-Have a 3 part body (Head, thorax, and abdomen)
-Have six legs (Hexapoda)
-Are the most diverse group of animals on earth
-Make up 90% of all diverse species on this planet
-Probably somewhere between 6 and 10 million species (Only one million named so far)
-The only invertebrates to evolve flight
-Usually when an animal evolves flight that group of animals evolves to have many species. The group of mammals that has the most species is bats. The reason is if you can fly you can travel and colonize new areas then your colony is subject to natural selection and sexual selection separate of your home colony.
-Most species co-evolved with flowering plants
-Because flowers provide nectar for insects and insects provide pollination to plants they have evolved very specific traits together.
Insect/Flower Example:
A Hammer orchid releases a scent that smells just like the pheromone of a female Thynnine Wasp. The orchid also looks like a female wasp. The male attracted to the smell and appearance of the flower tries to mate with it. The flower also has a hinge so when the wasp tries to mate with it the whole flower bobs up and down mimicking the mating behavior of the female wasp. This does not benefit the wasp at all but it does pollinate the flower.
Video:
Insects have many different life cycles depending on the species. Many of them go through a type of metamorphosis. Metamorphosis is one way we can classify insects.
There are three types of metamorphosis in insects
(Metabolous - coming from the word metabolic which is Greek for change)
Ametabolous metamorphosis
-There is no metamorphosis
-The juvenile looks exactly like the adult form
Hemimetabolous metamorphosis
-Partial metamophosis
-There is an egg-Nymph-adult stage
-A nymph looks very similar to the adult except it usually does not have wings
-A nymph goes through a small metamorphosis to become an adult
Holometabolous metamorphosis
-A complete metamorphosis
-There is an egg-larva-pupa-adult stage
-The larva looks completely different than an adult
-The larva has to create a pupa to turn into the adult stage
-A moth's pupa stage is a cocoon
-A butterflies pupa stage is a chrysalis
Class Discussion:
Why have a metamorphosis life cycle? It takes a lot of energy and insects are extremely vulnerable during the pupa stage. Why would it be beneficial to not hatch as a juvenile version of the adult? How is being a larvae a better strategy?
There are 24 orders of the class Insecta
Here are some important orders of the Class Insecta:
Ametabolous Insects
Subclass Apterygota - Insects without wings
(Greek - A for not or non and Pteron for wing)
Order Archaeognatha
-The oldest and least changed order of insects. Evolved only shortly after the arachnids. Is probably the first insects on land. The name archae (old) and Gnatha (jaw) refers to the order only having one mandible when most other insects have two. They have the ability to spring and jump.
-The jumping bristletails
Order Thysanura
-Greek - Thysanos - Bristle and Oura - Tail
-Very similar to the Archaeognatha except they cannot jump. They eat carbohydrate fibers which leads them to sometimes eat clothing.
-Silverfish
-Our oldest insect fossil looks like a silverfish and it dates to 396 million years old
Hemimetabolous Insects
Subclass Pterygota - Insects with wings
(Greek - Pteron - Wing)
Order Odonata
-Greek - odontos - Tooth (Because they have teeth on their mandibles)
-Elongate, membranous wings with netlike venation; abdomen long and slender; compound eyes occupy most of the head; hemimetabolous metamorphosis
-Dragonflies and damselflies
Watch and enjoy this short interesting video
Watch and enjoy this short interesting video
Infraclass Neoptera- Wings are folded at rest
Order Mantodea
-Greek - Mantis - prophet
-Prothorax long; prothoracic legs long and armed with strong spines for grasping prey; predators; hemimetabolous metamorphosis
-Mantids
European Mantid
Chinese Mantid Egg Sack
Chinese Mantids hatching from egg sack
Chinese Mantid Nymph
Watch and enjoy this short and interesting video
Order Blattaria
-Greek and Latin Blatta - cockroach
-Body oval and flattened; head concealed from above by a shieldlike extension of the prothorax; hemimetaboulous metamorphosis
-Cockroaches
Dubia Cockroach from Venezuela
Order Isoptera
-Greek - Iso same and pteron wing
-Workers white and wingless; front and hindwings of reproductives of equal size; reproductives and some soldiers may be sclerotized; abdomen broadly joins thorax; social; hemimetaboulous metamorphosis
-Termites
Watch and enjoy this short interesting video
NGSS Standard: Biological Evolution
Students who demonstrate understanding can:
HS-LS4-1.
Communicate scientific information that common ancestry and biological evolution are supported by multiple lines of empirical evidence. [Clarification Statement: Emphasis is on a conceptual understanding of the role each line of evidence has relating to common ancestry and biological evolution. Examples of evidence could include similarities in DNA sequences, anatomical structures, and order of appearance of structures in embryological development.]
New Superorder called Dictyoptera (Greek diktuon - net and pteron - wing) This superorder includes mantodea, blattaria, and isoptera
Watch and enjoy this interesting video
Order Dermaptera
-Greek - Derm Skin and Pteron Wing
-Elongate; chewing mouthparts; threadlike antennae; abdomen with insegmented forceps like cerci; hemimetabolous metamorphosis
-Show maternal care and guard their eggs
-Earwigs
Order Orthoptera
-Greek Ortho - straight Pteron - Wing
-20,000 species
-Forewing long; narrow, and leathery; hindwing broad and membranous; chewing mouthparts; hemimetabolous metamorphosis
-Grasshoppers, crickets, katydids
Watch and enjoy this interesting video
Order Phasmida
-Greek - Phasma ghost
-Body elongate and sticklike; wings reduced or absent; some tropical forms are flattened and leaflike; hemimetabolous metamorphosis
-Walking sticks, leaf insects
Walking Stick Eggs
Watch and enjoy this interesting video
Order Hemiptera (True Bugs)
-Greek Hemi - half Pteron - wing
-80,000 species
-Piercing-sucking mouthparts; mandibles and first maxillae styletlike and lying in grooved labium; wings membranous; hemimetaboulous metamorphosis
-Bed Bugs, Cicadas, Leafhoppers, Aphids
Watch and enjoy this short and interesting video
Watch and enjoy this short and interesting video
Watch and enjoy this horrifying video
Watch and enjoy this interesting video
Holometabolous Insects
Order Coleoptera
-Greek Koleos - Sheath Pteron Wing
-370,000 species
-Forewings sclerotized, forming covers (elytra) over the abdomen;; hindwings membranous; chewing mouthparts; the largest insect order; holometabolous metamorphosis
-Beetles
Darkling Beetle (Mill Beetle)
This is an optional video about why beetles are shiny
Watch this video on the pine beetle. Create a box in your sketchbook, title it "The Pine Beetle" and take notes, write down interesting things that you learn from the video and include an image in your sketchbook. We will talk about this beetle in class
This is an optional but interesting video
This is an optional video. If you are interesting in how bones are cleaned in museums, watch this video.
This is an optional video about underwater beetles
Order Lepidoptera
-Greek - Lepis - Sclales Pteron - Wings
-180,000 Species
-Wings broad and covered with scales; mouthparts formed into a sucking tube; holometabolous metamorphosis
-Moths, butterflies
Watch this video on caterpillars. Create a box in your sketchbook, title it "Hungry Caterpillars" and take notes, write down interesting things that you learn from the video and include an image in your sketchbook.
This is an optional but interesting video
Order Diptera
-Greek Di - two Pteron - Wings
-100,000 species
-Mesothoracic wings well developed; metathoracic wings reduced to knoblike halteres; variously modified but never chewing mouthparts; holometabolous metamorphosis
-Flies
SciShow: The wingless midge
This is an optional video
This is an optional but interesting video
Order Siphonaptera
-Greek Siphon - to suck Pteron wings
-100,000 species
-Laterally flattened, sucking mouthparts; jumping legs; parasites of birds and mammals; holometabolous metamorphosis
-Fleas, mosquitoes
Watch and share this video with as many people as you know so we can help reduce the mosquito population.
Watch this short and interesting video
Order Hymenoptera
-Greek Hymen - membrane Pteron - Wings
-150,000 Species
-Wings membranous with few veins; well-developed ovipositor, sometimes modified into a string; mouthparts modified for biting and lapping; social and solitary species; holometabolous metamorphosis
-Ants, bees, wasps
This is an optional video
Watch and enjoy this interesting video