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An imaginary look at the animal kingdom nesting boxes January 14 2020, 2 Comments

In my last post, I took readers on an imaginary tour of nesting boxes for the plant kingdom. These materials are traditionally called Chinese boxes, but I prefer to use “nesting boxes.” Children explore the structure and major lineages of a kingdom of life with this material. Nesting boxes work well for showing the lineages of the animal kingdom provided the content reflects current knowledge.

Here’s an imaginary tour of nesting boxes for the animal kingdom as it is defined today. I believe firmly that we should be giving children terms that they will see in their further studies, not terms that are historical and that do not appear in modern textbooks.

To start our tour, picture a large red box labeled “Animal Kingdom.” We remove the lid, and inside there is a small box that is labeled “Phylum Porifera, the sponges.” This group was once called the Parazoa, but this term has fallen out of favor, and I recommend these animals be called the sponges. Once thought to be several separate lineages, they are now placed on one lineage, Porifera (“the pore-bearers”).

Along with the little Porifera box, there is a much larger box that takes up most of the animal kingdom box. It is labeled “Eumetazoa, the true animals.” We lift the lid, and inside there are two small boxes labeled “Phylum Ctenophora, the comb jellies” and “Phylum Cnidaria, the stingers.” A large box labeled “Bilateria” takes up most of the remaining space, and it holds the animals with bilateral symmetry.

Cnidarians include the sea anemones, corals, and jellyfish. The comb jellies include sea gooseberries and sea walnuts. These two phyla were previously placed in a single phylum. That phylum, Coelenterata, is obsolete and should not appear in current animal kingdom classification studies. Our small red boxes are labeled “Phylum Cnidaria, the stingers,” and “Phylum Ctenophora, the comb-bearers,” and “Coelenterata” is not here at all.

The big box labeled “Bilateria, animals with bilateral symmetry” contains two boxes, which are labeled Protostomes (“mouth first”) and Deuterostomes (“mouth second”). These names reflect a difference in the development of the fertilized egg in these two lineages. The deuterostome box takes up about 1/3 of the space. We look inside it, and we find two boxes, one labeled “Phylum Echinodermata, the spiny skins,” and the other “Phylum Chordata, the corded ones.” The echinoderm box has the sea urchins, sea stars, and sea cucumbers inside. The chordate box has its three subphyla inside, the lancelets, the tunicates, and the vertebrates. Note that chordates are not the same as vertebrates! I’ve seen them mistakenly equated in Montessori materials. (If you find the term “non-chordate” in your materials, it would be best to change it to “invertebrate.”)

The protostome box has two boxes inside, one labeled “Spiralia” or “Lophotrochozoa” and one labeled “Ecdysozoa.” The Spiralia box has the rotifers, the flatworms, the mollusks, and the annelids (segmented worms). This box also has the name Lophotrochozoa although some biologists use this cumbersome term for only a part of the Spiralia. The term Spiralia could change so check again in a few years to see the current story. The Spiralia are named for the pattern of cells in the early embryos of most species.

“Lophotrochozoa” is still used for the Spiralia lineage in many college textbooks, but this could to change by the time elementary children reach college age. I have adopted “Spiralia” because of biologists’ support for it, and it is easier to spell and say. My book, Kingdoms of Life Connected, still has “Lophotrochozoa” because when I reprinted it last year, the term “Spiralia” was not yet shown in Wikipedia (usually a good source for the latest phylogeny). I hope biologists have settled on the name by the time I print the book again.

The ecdysozoa are the molting animals. They shed their whole outer covering at once. This is the most successful animal lineage in terms of numbers of species and numbers of individuals. The Phylum Arthropoda, the jointed feet, and the Phylum Nematoda, the roundworms, are the two main phyla in this box. Tardigrades and velvet worms could also go here if space allows and if you want to get that level of detail.

If any of your animal kingdom materials include “protozoa,” please remove them and study them with the eukaryotic supergroups (protists). They do not belong in the animal kingdom. If your nesting boxes for animals have protozoa, the best time to change this was about 40 years ago. The second best time is now.

I’ve presented a basic look at the animal kingdom here. If you would like further information on the animal kingdom or the lineages I gave in this article, please see my book, Kingdoms of Life Connected. https://big-picture-science.myshopify.com/collections/biology/products/kingdoms-of-life-connected-second-edition (printed) and https://big-picture-science.myshopify.com/collections/biology/products/kingdoms-of-life-connected-ebook-1 (pdf).

If you want to evaluate an animal kingdom chart, look for the groupings I gave for the nesting boxes. The nematodes should be grouped with the arthropods. The echinoderms should be grouped with the chordates. This is because biologists group organisms according to their shared ancestors, not just how they look. The chart from InPrint for Children places related phyla next to each other. See https://big-picture-science.myshopify.com/collections/biology/products/animal-kingdom-chart.

My photo card set for the animal kingdom - https://big-picture-science.myshopify.com/collections/biology/products/zoology-photo-cards-set-1-major-phyla-of-the-animal-kingdom – gives you high quality images of representative animals across the kingdom. They could be used in or alongside a nesting box material.

Happy explorations of the animal kingdom,

Priscilla

 

PS. I am putting my reply here to two comments below. I'm sorry I don't have pictures of this imaginary material for you, Gail. I, too, am a visual learner. I think Cindy's idea of referring to the animal kingdom diagram from my Tree of Life chart might help. Yes, the lids on the boxes would be like a node on the evolutionary tree (phylogeny). The reason that there isn't a box for the Radiata is that they don't seem to share a common ancestor other than the one for all animals. If they did share a more recent ancestor, they might still be in Coelenterata. They have a similar organization, although the ctenophores are described as biradially symmetrical. They have a combination of radial and bilateral symmetry. The cnidarians are genuinely radially symmetrical. These two phyla came from separate experiments by early animal life. This is different than the the two phyla shown in the Ecdysozoa. They shared a common ancestor - at least there evidence for this in their genomes. 

Thank you for sending your questions and comments. Please feel free to ask further questions.  


Octopuses and other animals April 14 2015, 0 Comments

There’s a great new book out called Octopuses! Strange and Wonderful. It is by Laurence Pringle and is illustrated by Meryl Henderson. Together they present an attractive, accurate, and informative book about octopuses and other mollusks as well. The book would be an engaging read-aloud for younger elementary children and a good research material for upper elementary. I liked the information about how mollusks’ bodies are structured and how they work. Obviously this author researches his subjects carefully, and he knows how to tell a good story as well.

When I looked on Laurence Pringle’s website, I discovered that he has produced many highly rated children’s science books. The Strange and Wonderful series includes books on scorpions, cicadas, alligators and crocodiles, snakes, bats, and sharks. I was familiar with another high quality book by this author, A Dragon in the Sky: The Story of a Green Darner Dragonfly, published in 2001. I’m not sure how I missed the Strange and Wonderful series, but I will certainly seek it out now.

Another volume I have acquired lately is Animal Earth: The Amazing Diversity of Living Creatures by Ross Piper. It has many uses, from providing gorgeous illustrations of all sorts of animals to giving detailed biology for secondary student research. When I say all sorts of animals, I mean that the book covers all of the 34 phyla currently recognized in the animal kingdom. There is a chapter on animal lineages that helps one understand the current arrangement of those phyla on evolutionary trees (cladograms). The book is structured to follow the cladogram in the contents page. After the first branches of animals, the section on bilaterial animals starts with deuterostomes, and so the chordates, including us, are near the front of the book. Then it covers the protostomes, starting with the molting animals, including arthropods and nematodes. The clade called lophotrochozoa comes next, with annelids, mollusks, flatworms, and rotifers. The order alone will stimulate thought.

I found What on Earth?: 100 of Our Planet’s Most Amazing New Species while I was browsing in a bookstore. I highly recommend spending some time going through the stacks at bookstores, particularly those with a science section. I find things there that I missed on Amazon. This little book by Quentin Wheeler and Sara Pennak will likely stimulate conversations and research about a wide range of life. The 100 species are primarily animals, but fungi, plants, and a few protists also appear. There are even two bacteria. A feast for curiosity indeed.