FOSSIL INVERTEBRATES by Paul D. Taylor and David N. Lewis. Cambridge, Mass.: Harvard University Press, 2005. $35.00 hardcover; 208 pp; 5 page appendix; 1 page of sources for further information and websites. The book is illustrated throughout with black & white photographs as well as 39 color plates.
Taylor and Lewis state that their purpose in writing Fossil Invertebrates is to "introduce examples of the more common invertebrates from around the world, as well as some rarer but scientifically significant fossils. We have set out to highlight the appreciation of fossils as the remains of once living animals, not merely as oddly shaped stones." (p.4, Fossil Invertebrates) They have accomplished this goal in laudable fashion and it is for this reason that this work is notable.
The eleven-page Introduction covers much of the basic information beginning with an explanation of what is and what is not a fossil. Part of this chapter deals with the types of rocks that contain fossils and how sediments become rocks. Fossil formation and preservation is well covered. Dating of fossils and the geologic timescale are explained in some detail.
Following the Introduction, subsequent chapters are divided into main groups: Living in Colonies, Shells Galore, Worms and Tubes, Jointed-Limbed Animals, and finally Spiny-Skinned Animals. The chapter categories are not necessarily biological in nature but have been constructed by grouping animals of similar appearance or lifestyle habit. Within each chapter is a general introductory section that relates much about what types of animals belong in the group. This is where Taylor and Lewis excel for it is here that they relate the biology of the living forms and connect them to what we see as fossils. As you may imagine, this includes body style and growth, feeding and reproductive methods, and relationships with other groups. Following this, subgroups are discussed in similar fashion giving more in-depth coverage. The subgroup discussion is followed by a number of specific fossils with pictures and a technical morphologic description.
A chapter has any number of subgroups within it that are organized in this way.
Despite the American heritage of the Harvard University Press, the authors are both with the Natural History Museum, London. Taylor and Lewis have a number of British fossils illustrated but the book is worldwide in scope so that examples from all over the world are presented. Of local interest, fossils from the Cincinnatian are nicely represented either in the text or as selected illustrated fossils. The Cincinnatian Streptelasma [Grewingkia] horn coral gets special note in the colonial organisms section as does the abundance of trepostome bryozoan colonies. The Cincinnatian is again highlighted with an illustration of the local sponge Brachiospongia from Kentucky. Rafinesquina gets an illustrated description with the brachiopods. The edrioasteroid Carneyella rounds out the local fame.
Colonial animals appear first in Living in Colonies. Cnidaria (including corals), bryozoans, sponges and graptolites are all well explained. Interestingly enough, there is as much text and as many illustrated specimens devoted to graptolites as there is on trilobites in the Jointed-Limbed Animals chapter in Fossil Invertebrates.
Stromatoporoids are mentioned in the colonial organism section classified as sponges. Stromatoporoids had calcareous spicules rather than the siliceous type we are more familiar with. In a sidebar, the authors explain that the stromptoporoids belong in the sponge class called Demospongiae although they allow that they are usually placed in their own class of Stromotoporoidea. A nice sectioned specimen from the Devonian of Australia is illustrated on page 49. At least from the photo it looks strikingly similar to sectioned specimens from the Cincinnati Ordovician.
Shells Galore is the chapter covering brachiopods and molluscs. As I mentioned earlier, putting these two groups together does not imply biological relatedness. I am certain this was done as the two groups share some morphological and behavioral similarities. As I am not a brachiopod expert, I was surprised to see the classification that I am familiar with has been changed. No longer are the brachiopods divided into articulates and inarticulates. It seems that the inarticulates have been broken into Linguliformea and Craniiformea while the articulates are now referred to Rhynchonelliformea. Other subsections in this chapter cover the bivalves, gastropods, nautiloids and ammonites. Also discussed are the less well known molluscs: monoplacophorans, bellerophontids, polyplacophorans, rostroconchs, and scaphopods - a number of these are to be found in the Cincinnatian.
The chapter Worms and Tubes will give the reader a better appreciation of the locally abundant Scolecodont worm jaws. As in all chapters, Taylor and Lewis explain related living organisms and what is available in the fossil record and what is not. Two enigmatic forms, the Cornulitids and Tentaculitids, are included in this chapter. The Tentaculids are the most problematic of these two as the authors reveal that there is no consensus on their relationship to other invertebrates. Some put them with molluscs while others place them with the lophophorates (brachiopods, bryozoans and phoronid worms, p.134, op.cit.). The chapter closes with the even more puzzling group, the Hyoliths.
Trilobites are included with the other arthropods in Jointed-Limbed Animals. While other books specializing in trilobites cover them in much more detail, Fossil Invertebrates provides a good summary of what is known about their physiology and lifestyle. No local trilobites are illustrated but there are a number of similar forms from around the world. Most fascinating were the descriptions of trilobite feeding habits that have been deduced in part by their morphology. An interesting bit of information here was new evidence of trilobite predators. Taylor and Lewis report of direct evidence that a Chinese fossil of an unknown predatory Cambrian animal had trilobite fragments in its gut (p.143, op.cit.).
Chellicerates (spiders, scorpions, horeshoe crabs), Crustaceans (crabs, lobsters, barnacles, ostracods), Myriapods (millepedes and centipedes), and insects round out the arthropod chapter. Of note here is the reporting of the oldest confirmed insect fossil from the Devonian of Scotland dated between 400 to 412 million years ago. Even though this is the oldest known insect fossil, Taylor and Lewis tell us that Rhyniognatha hirsti has enough "advanced characteristics" that insects may have evolved even earlier in the Silurian (p.160, op.cit.). Unfortunately, the authors decided not to illustrate this intriguing fossil. Fossil Invertebrates ends with a chapter on echinoderms, the spiny-skinned animals. The more well known echinoids, crinoids, ophiuroids and asteroids are covered as well as cystiods, blastoids, eocrinoids, edrioasteroids, cyclocystoids, helioplacoids and carpoids that have no extant descendants.
New studies resulting in changes to classifications happen in all areas of paleontology. Here we learn that the Cambrain fossil Echmatocrinus once considered to be the earliest crinoid has been re-classified as an octacoral. That's quite a change.
Of the six crinoids selected for illustration in this section, five were from England. The sixth was Saccocoma from the Jurassic of Solnhoffen - an interesting form but not all that spectacular in a photograph.
This is the only place I noted the authors favoring British specimens over possibly better worldwide examples.
Despite my issue with the crinoids, Taylor and Lewis redeem themselves in the edrioasteroid section with "Upper Ordovician deposits in the Cincinnati region of the USA are particularly well known for edrioasteroids" (p.192, op.cit.). They go on to describe the conditions of their occurrence and preservation.
Only three edrioasteroids are pictured and described including a nice Carneyella from Kentucky.
Overall, the general reader will gain the most from the discussions preceding the descriptions of specific fossils. Fortunately, this is the bulk of the book and the prime reason for reading Fossil Invertebrates . The specific descriptions use too many undefined technical terms that will not be helpful to a non-specialist. On occasion, even the broader text contains some undefined terms but I did not find this to be excessive.
Readability - Undergraduate with biological background because of terminology.
On the Upside - Beautifully photographed specimens of both living and fossil forms. The text describing the general nature of each type of organism defines most necessary technical terms in context. These portions link the biology of the organisms to the more familiar fossil remains.
On the Downside - Undefined technical terms are used to describe the selected individual fossils at the end of each section. Even though these descriptions are abbreviated from those used in professional publications, their complexity will leave the general reader baffled. Even the authors point out that the descriptions are not as complete as professionals require. I have to ask then what purpose do these semi-technical descriptions serve? Because of this issue, I was unsure of the intended audience - the book is not technical enough for professionals and the descriptions are too complex for the general reader. To quote one of our local professional paleontologists, "the purpose is to educate, not obsfucate."
Overall Rating - Recommended as a useful and valuable resource for the general reader interested in gaining a better understanding of the once living animals whose remains we now collect as fossils.