I have a couple of objectives for today:

Review the structure and objectives for this course

Answer the question: why study invertebrates?

In the syllabus, I have stated the objectives (or goals) for the entire course.

This is Biology 322 (lab 323), Invertebrate Zoology.

I’m Matt Persons

Call me Matt or Dr. Persons--whichever you are more comfortable with.

My office hours are 11-12 MWF right after class and by appointment. You can hop in and see if I’m available anytime too. I don’t mind if you stop in whenever.

I just have to say, I love teaching this course because I love this stuff--invertebrates are infinitely more interesting than vertebrates--and I hope to convince you of this by the end of the course.

The animals I’ll be discussing with you are more bizarre and interesting than anything you’ve seen in a science fiction movie-and for most of these creatures there is little known about them. Some of them you have probably never heard about because they are rare, have little economic value, or are simply understudied. There biology can often be nothing less than astounding. Many invertebrates you have probably never heard about because they are perpetually slighted at every zoo exhibit in the country and you never see them on a national geographic special "Nematodes of the Serengeti" Perhaps this is because we gravitate toward animals we can relate too--vertebrates, but the biological differences between invertebrates and ourselves makes them much more interesting I think.-Kinorhync males produce sperm a fourth of the size of their body" or Sea cucumbers are known for breathing out of their anus". For Example, here is a bizarre fact about a rather inconspicuous group of worms that makes us reconsider what we know about sex determination. Among members of the phylum Echiura-a poorly understood group of marine worm-like animals, sex determination does not occur upon fertilization. Instead, for most individuals, maleness is induced only after contact of the larva with the proboscis of an adult female. In the absence of such contact, larva become female. Weird huh. Well, I don’t want to give away all the cool stuff on the first day, I just wanted to whet your appetite for some of the biology of all these amazing creatures.

Format: Lecture and Laboratory

Things to get:

Pechenik (is it in?)

You also need a dissecting kit for lab that you have probably already acquired at some point in some other biology class.

I would like to apologize for the excessive cost of the text book. But I’ve made some reparations for this hopefully.

The lab book you will receive free of charge-and only covers essential information. It is provided free of charge.

This is one of many courses at Susquehanna where you actually get MORE than you would expect-- worth of stuff.

Lab book: $12.00/student

Dissection Material: $20.00/student

Live invertebrates: $30.00/student

Visual aids/slides/demonstration material: $15.00/student

Now-I’ll address the stuff that students always want to know about--

Grading and Succeeding in this class:

How to succeed in this class:

1) prepare: read the text

read the lab manual before lab

bring text to lab for reference

2)participate: do all the lab exercises

stick around and learn something extra

ask questions

think critically about what is being discussed

show up.

3) pay attention: review with others before exam

work through study guides for exams

LECTURE

The lecture draws on numerous sources-

Use the book Pechenik as a good reference book and paperweight. Use it as a guide for this course. There is an ENORMOUS amount of information in the subject of invertebrate zoology-far too much to cover in a single semester. You are expected to read the book from cover to cover, but short of that, use it to look up information I present and fill in any gaps in your knowledge base since the course covers aspects of behavior, development, ecology, phylogenetic systematics, natural history, anatomy and physiology, as well as reproductive biology. Some of this information I will assume you already know after taking introductory biology classes here. I will try to refresh your memory on some topics however. I will also give out a study guide before lecture exams to emphasize important topics and let you know what to expect. Also I will be reiterating common conceptual themes throughout the course and you hopefully will pick up on these topics as being important.

There are three lecture exams worth equal number of points. The final is not comprehensive except that there will be a "grab bag" question that will be given during the last laboratory practical. This question will consist of pulling an invertebrate out of a cloth sac and telling me about its reproductive biology, respiration, excretion, feeding habits, ecology, taxonomy and stuff like that. All exams will be composed of a mix of short answer, multiple choice, definitions, matching, and a choice between 2 long essay questions. For the final, that essay question will be take home.

Extra credit? Yes---for 20 points you may keep an invertebrate of your choosing for the entire semester (or as long as it lives).

You will need to find out the following information on your invertebrate:

Full taxonomic designation--including:

Phylum, Class, Order, Family, Genus, and species

Phylogeny (what groups are most closely related to it).

How it reproduces

How it eliminates waste

How it respires

How it eats (at all stages of development)

How it develops

How it moves

Names of all locomotory and sensory appendages (if any)

How it perceives the environment (sensory organs)

Where it lives (microhabitat needs)

Its biogeography (what is its distribution in the world?)

Natural history (how long does it take to reach adulthood, how many offspring does it produce, how many times does it mate, how long does it live)

What are its predators and defenses against predators

How did you keep it alive?

I strongly urge all of you to participate--give me an animal name as soon as possible.

A note about this course---many of the animals we will be discussing are poorly known. I may not tell you aspects of an animals life cycle for example--because we currently don't know anything about its life cycle.

LABORATORY

Course outline and timing of exams. The first two lab practicals should be about 30-40 minutes long. The last one will be a little longer because it will have a portion of the lecture exam incorporated into it. These are your basic lab practical types of tests-identify taxonomically different animals, identify dissected specimens, look at slides, that type of stuff. I will go over the lab practical format in more detail at a later date and in the laboratory portion of the course.

Invertebrate Zoology is known as the course on creepy crawlies.

I’ll pose a question to you: Class question: Why study invertebrates? why did you sign up for this course?

Here are some of my reasons for studying inverts.

Invertebrate zoology has been a victim of unfounded prejudice. The very nature of the subject-animals without backbones implies the basis of the bias. It is only because we ourselves possess a backbone that this arbitrary division is made.

Vertebrates make up a rather small, almost insignificant portion of the total species of animals on the planet. so it is strange that we should choose to dichotomize the species in this way. Wouldn’t it be much better and much more equitable to divide the animals into those with elytra and those without? or beetles and non-beetles?

or perhaps animals with three tagmatized regions of the exoskeleton and those without (insects).

Invertebrates, by most estimates account for between 94 and 99% of all animals on the planet. Based on this fact you can think of this as a course in general zoology as much as invertebrate zoology.

Now consider a further breakdown of the numbers of species of the different phyla on the planet

Show Fig. 2.9 Pechenik

Notice the chordate box. The colored area represents the vertebrate chordates. Bear in mind that not all chordates are vertebrates.

Since invertebrates make up the vast majority of known (and almost certainly unknown) species as well, one would think we know a great deal about them.

Certainly since there are so many, that means that we can only cover a tiny percentage of the information that these animals have to offer. By necessity this course will be skipping a rock across the ocean of knowledge concerning invertebrates.--but at the same time how much do we really know about invertebrates relative to other groups?

Well, just a little survey of how much we know about different phyla based on publication rates of articles in major journals. Here is a comparison.

The moral of this story is that not only do I know nothing about invertebrates in the grand scheme of things, but neither does anyone else. And you may ask me questions from time to time that have no easy answers. or are simply unknown. No one knows the life cycle of Kinorhyncs The first rule of invertebrate zoology is there are no rules. Or put another way, for every generalization, there is an exception. The literature is enormous. We can’t cover it all. But, we will cover a little bit about everything. -to skip a stone across the ocean of knowledge about invertebrates.

This is why I study invertebrates-because there is very little known about them-it’s like exploring a new universe.

Some people need applied or economic reasons for studying invertebrates however. Here are just a few that I thought of off the top of my head. There are others. SHOW OVERHEAD

Invertebrates are important in biological research.

Why use Drosophila to study genetics?

or C. elegans or sea urchins for development?

1) they are small in size

2) they can be very simple structurally

3) they have a short life span and reproduce rapidly

4) easily available, often easy to maintain

Developmental studies are well known with sea urchins and nematodes

Planarians are used in studies of regeneration

hormone interactions have been examined in many insects

Physiology-insects, molluscs play a major role. Squid neurons are among the largest in the world and for this reason have been used in nerophysiology for years

Immunobiology and comparative immunology-anyone in the Karp lab can testify to the use of invertebrates in this regard-since they use cockroaches as an easy system to study inducible immune responses

In ecology studies, the classic example of competition experiments have involved Paramecia and Tribolium beetles.

Mate choice, game theory, foraging and other behaviors are often applied to invertebrate models to understand the simplest explanations for observed behaviors.

Genetic studies: Drosophila is an easy example

Evolutionary biology-consider B. betularia, the peppered moth as the classic example of natural selection. Kane’s lab has been working on Gammarus amphipods as a model of understanding how gene flow, genetic drift, and natural selection may interact with each other.

Now what have we gotten out of all these studies?

Crop pollination (bees)

Chief competitors for food (especially insects, mites, and nematodes)

Pest control (parasitoid wasps, beetles, spiders, parasitic nematodes of insects)

Weed suppression (some insects)

nutrient enrichment/soil aeration (oligochaete worms)

Symbiotic nematodes (both parasitic and mutualists) of plants

Biomonitors of pollution-aquatic insect larvae

Mechanisms of pattern formation during embryonic development (Caenorhabditis elegans).

transmission of nerve impulses

biochemical basis of learning and memory

biology of vision

mechanisms by which genetic diversity originates, and is maitained

Many invertebrates are parasites and disease carriers (tapeworms, pinworms (currently there areEnterobius pinworm:50,000,000 cases of Enterobius infected people in the U.S.--in other words--1 in 5 Americans have had pinworm; 500,000,000 worldwide in temperate areas), malaria (300,000,000/year -3 million of those infected die/year), schistosomiasis (infects 300,000,000 million worldwide, etc. human hookworm (Necator) infects 900 million people worldwide, guinea worm, dog heartworm, river blindness infects 40 million people worldwide, plant parasites kill

Chinese liver fluke (Opistorchis infects 20,000,000 East Asians).

Medicine production -antitumor agents from marine sponges

Bioassays for disease-Sipunculan worms serve this purpose to diagnosis people with acute cholera and cystic fibrosis (E. Cutler, 1994-The Sipuncula)

Hirudin from leeches serves as an anticoagulant for strokes, heart disease patients and reattachment of amputated limbs.

Horseshoe crab eyes serve as the model for the development of high definition television.

Invertebrates are also are chief competitor for food (particularly insects, mites, and nematodes)

Sunscreens (corals)

Instant adhesives (onychophorans, spiders, centipedes)

Marine adhesives that are non-corrosive (barnacles and deep-see worms)

Flexible concrete (molluscan shells adapted to wave action)

Light high tensile strength fibers (spider silk (stronger than steel).

Invertebrate Importance in Ecological Systems

Invertebrates occupy virtually every available niche on all continents and all ocean depths.

Frequently the basis of many food chains

Plankton

Zooplankton serves as a basis for most marine life (above phytoplankton of course)

Coral reefs serve as a basis for one of the most productive ecosystems on earth with the exception of rainforests and serve as a basis for such ecosystems.

Herbivores (the majority of which are insects) turn over hugh amounts of energy. They greatly affect plant competition and evolution.

Since most invertebrates are middle links in food chains (or otherwise serve middle trophic levels), they tend to stabilize ecosystem dynamics.

Decomposers/and reducers -arthropods, molluscs, nematodes, and annelids play a major role in nutrient recycling and breakdown of organic matter in many ecosystems.

This course is covered from an organismal biology perspective. The animal is more than the sum of its component parts. It is upon the individual that natural selection acts, and therefore to understand the adaptations that it shows must be considered from a whole animal perspective.

We will be considering the different types of animals that we see from the following perspective:

What kind of animal is it?

What does it do?

Where does it live?

What is it’s ecological role (predator? parasite? detritivore? filter feeder?)

How is it adapted to live where it does and eat what it eats and do what it does?

We will answer these questions by looking inside the animal-

anatomy, physiology, morphology, organs, functional design

and outside the animal-

the environment of the animal, competitors, evolutionary history and relationships, dispersion patterns etc.

I’ve briefly given you some reasons for why you should know about invertebrate animals. I’d like to leave you with a question to think about for when we meet again-I have an informal assignment---Question: What is an animal? How do you distinguish it from other types of organisms? Just have a reasonable answer or a best guess by next week--nothing to turn in--just a best guess.