Inverterbrate Project

Hummingbird Clearwing Moth 

Hemaris Thysbe

 

The Hummingbird Clearwing Moth is one of nature's very best examples of mimicry and delicate beauty. Like the hummingbird, it hovers in the air to sip nectar from sweet flowers, beating its wings at rapid speeds so fast that they seem a blur. Although these moths share many similarites with the Hummingbird, that is not why they are called Hummingbird Moths. It is because, when sighted, they are often mistaken for hummingbirds themselves!

Phylum: Arthropoda
Class: Insecta 

Essential Functions

1) Body Structure
Adult Hummingbird Clearwing Moths grow to about 2 inches in length with wings that span 1-2 inches. Their thorax is olive in colour dorsally, and yellow ventrally, with a burgundy coloured abdomen ending in a fan-like tail of setae. The moth has one pair of compound eyes, one pair of strongly clubbed antennae, six legs and a proboscis. Their most interesting physical feature, as denoted by their name, is their clear wings. Their wings are scaled like most moths when they first leave their cocoon, but once they have taken first flight, the scales fall off and leave behind beautiful clear wings rimmed with orange-burgundy borders and veins. Hummingbird Clearwing larvae are most commonly green, brown and gray, but other colours do exist.

2) Digestion/Feeding

Adult Hummingbird Moths snack on the nectar of their favourite flowers. These include Japanese Honeysuckle, Beebalm, Red Clover, Lilac, Phlox, Snowberry, Cranberry and Blueberry plants and Thistles. Their larvae enjoy the leaves of these same plants. An adult moth uses a specialized mouthpart, a long, thin, needle like proboscis to suck up the nectar.

Like all moths, the Hummingbird Clearwing Moth's digestive system consists of a foregut, hindgut and midgut. After nectar is sucked up through the proboscis, it is passed into the esophagus and then stored in the crop for a short time. After this it continues on to the gizzard and then through the valve to the midgut and to the stomach where main digestion and absoption of nutrients takes place. The hindgut will then absorb the  water and nutrients from the nectar that the midgut did not and pass the waste out through the anus.

3) Circulation
 Hummingbird Clearwing Moths have an open circulatory system where blood is passed through blood vessels and body cavities called sinuses. Moth blood is actually green due to the fact that it is not oxidized when carried through the dorsal vessel. The moth has one heart that pumps blood to the rest of the body.

4) Respiration
Hummingbird Clearwing Moths breathe through thoracic and abdominal spiracles connected to tracheal tubes that diffuse oxygen to all body tissues and diffuse carbon dioxide out of the body through the spiracles.

5) Excretion
Moths excrete food wastes out through the anus. They also possess a set of Malpighian tubules which eliminate nitrogenous wastes from the blood, passing them out through the anus along with food wastes.

6) Movement
Hummingbird moths have a very unique way of moving unlike any other moth in their order. Their wings are made of many thin layers of chitin and they beat them very rapidly to hover in the air. Their wings can reach speeds of 30 beats per second and 30 miles per hour!

7) Reproduction
Hummingbird Clearwing Moth reproduction is internal and the moth breeds an average of 2-3 times per years. The moths detect mates by smell and sight, and once found, have been known to engage in a courtship chase in which the male and female fly through the air spiralling upward or flying low to the ground. Once the female's eggs are fertilized, she will lay them on a host plant. A host plant is one that the hatched larvae can feed upon (leaves) and are often the same plants it feeds on in adulthood. (nectar) The female Hummingbird Moth can lay up to 200 eggs, each on a different host plant! The eggs hatch into larvae within 6-8 days and after a while undergo complete metamorphosis, spinning a loose,glossy cocoon from which it will emerge an adult Hummingbird Clearwing Moth.

Other Important Information

• Hummingbird Clearwing Moths are bilaterally symmetrical.
• They have 3 germ layers: the mesoderm,(a middle layer of cells that forms
  the muscles and interior organs) endoderm, (cells on inside of gastrula that become the lining of the gut) and ectoderm. (cells on outside of gastrula that become the body covering). 

•  Other organsims found within the same phyla as Hummingbird Moths (Arthropoda) include beetles, centipedes, spiders, butterflies, grasshoppers and many, many more.
• Hummingbird Moths are protostomes. In protostome development, the embryo forms a dent on one side called the blastopore which deepens to become the archenteron which is the first growth of the gut. The original dent becomes the anus of the moth and the gut tunnels through the embryo to form the mouth of the moth.

Ecological Significance

• Hummingbird Moths are important pollinators and aid in seed production.
• They are food for a variety of wildlife including other insects, spiders, frogs, toads, lizards, shrews, hedgehogs and birds. That is, IF they can catch them!
• Hummingbird Moth caterpillars eat certain plants' leaves, causing them to evolve characteristics which make them less appealing to the larvae. An example might be developing bad tasting chemicals on the surface of its leaves that deter the animals from eating them.
• Hummingbird Clearwing Moths are useful as an indicator species as they are so abundant but are also quite sensitive to environmental change. 

Interesting Facts 

• Hummingbird Clearwing Moths are seen on clear, sunny days unlike most moths because, like humans, they are diurnal and sleep at night.
• The Hummingbird Moth mimics the Hummingbird in order to trick predators into staying away from it.
• It lives in Alaska, the Northwest Territories, BC, Oregon, Maine, Newfoundland, Florida and Texas.  
• Hummingbird Moths are known for being quite comfortable around humans and some will even land on you if you have some tasty nectar to offer!

 So why do I love Hummingbird Clearwing Moths? Because they defy our expectations with their fascinating mimicry and are adorable little creatures.

Squid Dissection

Last Friday our Biology class dissected a mollusk, one that is abundant in most marine environments, and is even one of the main characters on the popular kid's show, Spongebob Squarepants. We dissected Squidward, or at least someone related to him; a fifth cousin perhaps?

A squid is a cephalopod. In Latin this means "head foot". It sounds a little strange, but the name is actually quite logical. A squid really is just a head attached to some feet! Octopi are another well known species of this phylum. The two other types of mollusks that can be seen are known as Gastropods and Bivalves. One of the most common Gastropods in existence is the garden snail. Gastropods are "stomach feet", as their stomach is literally just above their feet inside their bodies. The next species in the phylum Molluska are the Bivalves. Their name means "two shell" as they possess two shells that can be tightly closed with strong muscles. Many of our most delectable seafood items, like clams and oysters are bivalves. It is interesting to note that although these forms are radically different from each other phenotypically, they all share specially evolved shells and feet. In fact, this is how they are classified. The squid, for example, has hardly any shell externally, but has a small plastic-like tube inside of it called the pen which is what is left of the squid's shell after evolution.

The squid has a most interesting internal make-up. Its insides are quite jelly like, save for the hard pen, and its ink sac looks quite a bit like a small minnow that has not yet been digested by the squid. It has a closed circulatory system rather than an open one like the bivalves as an open system is not conducive to free swimming and active animals such as squids. They possess advanced vision and brains and will secrete an ink cloud when threatened. It is difficult to explain the various features of the squid,  and how its internal organs function. Dissecting the squid allows us a first hand look inside its body, a real life explanation of its complex inner workings. Squids are fascinating   creatures and there is so much more to them than one sees as they glance into the plastic case at the T and T supermarket, and that is why dissection is so helpful to one's understanding of internal biology.

Our squid had 8 arms and 2 tentacles.

 The squid uses arms and tentacles for different purposes. Tentacles serve to help the squid grab prey and hold on to it and also play a role in mating whereas the arms are used to aid in feeding and grasping prey once it is in close proximity to the beak. Suckers on the arms are bigger than those on the tentacles.

 Forgot to take a picture for this one. To move, the squid draws water up into its mantle cavity and then expels it through the funnel creating jet propulsion. The squid can move either forward or backward.

Our squid's eye. Its eyes and tentacles are both adaptations for its predatory life. Its light-sensitive eyes allow it to see prey even in the darkness of the depths of the ocean, and its tentacles allow it to catch prey by surprise, snatching it at high speeds from far away.

Two traits that the squid shares with other mollusks are the presence of a mantle and of a visceral mass. Although all mollusks also have a foot, it is highly specialized and evolved to each mollusk's needs and thus looks different for every species.

The squid has 2 pairs of gills, one on each side.

The ink sac empties into the siphon and out of the squid's body into the surrounding water. Its function is to allow the squid camouflage in a dangerous situation so that it can quickly swim away from a predator.

This is the pen of our squid. The function of the pen is to give the squid structural support. It is considered a vestigial structure, so the squid's functions would most likely not be impaired were it not to have a pen.

As squids do possess a full digestive system, wastes exit the squid through the anus.

Earthworm Dissection

Last Friday, we dissected an earthworm in class. Although slightly icky, dissecting the earthworm allowed us to see first-hand the various parts of an annelid's nervous, respiratory and digestive system. The purpose of the dissection was also to improve our understanding of an annelid's internal organs so that we could identify them based on shape and function. 

Before learning about annelids, I had no idea that earthworms even had organs, so the dissection was also beneficial in improving my understanding of the living world around me. I learned that earthworms do in fact have a nervous system and even a primitive brain composed of ganglia as well as a ventral nerve cord that runs the length of their body. Additionally, I learned that worms in fact breathe through their skin and that that is why they are constantly moist. Earthworms also have two blood vessels and five hearts. Had my partner and I not punctured the crop and gizzard of the worm, we would have been able to see more of these fascinating things, but at least we now know that surgeon would not be a good professional choice.

None of these systems are apparent from the outside, and it is interesting to note that even the simplest and most overlooked animals are quite complex beings on the inside.

The name of the pumping organs in an earthworm are the aortic arches.

The process of digestion in an earthworm necessitates the involvement and cooperation of many different organs. Food is ingested by the earthworm and then travels to the pharynx which pumps a mixture of food and soil into the esophagus. The food-soil mixture is then transported to the crop for storage and continues on to the gizzard where it is ground up into small pieces for more effective digestion by the intestine. Any undigested materials pass through the worm's intestine out through the anus in solid form.

The two large nerves that pass around the gut of the worm and connect the brain with a pair of ganglia are also attached to the ventral nerve cord that runs the length of the worm's body. These parts, the ganglia, nerves and ventral nerve cord make up the nervous system and the ganglia above the pharynx serve as the worm's brain.

The intestine and nephridia are included in the worm's excretory system. They both remove waste products from the body. 

The easiest way to find out if an earthworm eats soil is to examine its excrement or castings. Because the soil is indigestible, it will come out in the excrement as a grainy substance.

Four pairs of earthworm setae. The earthworm's setae are very useful tools for the worm as its habitat is soil and sediment. It must burrow through the soil and sediment, and this is difficult without something like setae to anchor them in the soil. Setae are especially useful as a defense mechanism against animals which try to pull the worm up from the soil.

The earthworm's digestive system is adapted for extracting relatively small amounts of food from large amounts of ingested soil. This is possible due to the gizzard of the worm which grinds up food particles into smaller pieces and then passes them on to the intestines where food is absorbed and soil is excreted through the anus. 

If we dissected the remainder of the worm to the posterior end, we would have observed the continuation of the intestine, the ventral nerve cord, and at the very end, the anus.

The earthworm's reproductive organs have certain roles and functions in order to carry out reproduction successfully. Because earthworms are hermaphrodites, they produce both sperm and eggs. Eggs are produced in the ovaries and sperm are produced in the testes. During reproduction, two worms connect at the clitellum and exchange sperm through their male genital pores. After copulation has occurred, the clitellum secretes a mucus-like cocoon which the worm slips out of, its eggs and the other worm's sperm being injected inside the cocoon through the female and male genital pores as the worm escapes it. Once the worm has left the cocoon, its ends close and embryonic worms begin developing.


NOTE: These pictures are from google. I did have some pictures on my phone of the actual dissection, but I was unable to upload them. 

Zoology Webquest

Porifera

An Azure Vase Sponge.
Genus: Callyspongia
Species: Callyspongia plicifera
The Azure Vase Sponge's colouring ranges from pink to purple and fluorescent light blue.

A Barrel Sponge.
Genus: Xestospongia
Species: Xestospongia muta
Barrel Sponges are known as the "Redwoods of the Reef" due to their 2000 year life span, size and colouring.

A Row Pore Rope Sponge.
Genus: Aplysina
Species: Aplysina cauliformis
This sponge inhabits lagoons and deep sloping reefs.

Cnidaria

The Tealia Anemone.

Genus: Urticina

Species: Urticina Crassicornis
The Tealia Anemone may feed on crabs, sea urchins, mussels, gastropods, chitons, barnacles, fish, and sometimes sea stars and stranded jellies.

The Lion's Mane Jellyfish.
Genus: Cyanea
Species: Cyanea capillata
The Lion's Mane Jellyfish is the largest known jellyfish. It lives in the cold water of the Arctic, the northern Atlantic, and northern Pacific Oceans.

A Pacific Sea Nettle.

Genus: Cryasaora

Species: Chrysaora fuscescens
Pacific Sea Nettles live in the East Pacific Ocean from Canada to Mexico.

Platyhelminthes

The Persian Carpet Flatworm.

Genus: Pseudobiceros

Species: Pseudobiceros bedfordi
The Persian Carpet Flatworm eats ascidians and other crustaceans.

The Fuschia Flatworm

Genus: Pseudoceros

Species: ferrugineus 

The Fuschia flatworm can reach a length of about 18-48 mm.

The Tiger Flatworm

Genus: Maritigrella

Species: Maritigrella crozierae

 Maritigrella crozierae is common in the Indian River Lagoon where it feeds exclusively on the mangrove tunicate, Ecteinascidia Turbinata.