January 2005] Reviews Trivers's Theory Of

January 2005] Reviews Trivers's Theory Of

January 2005] Reviews 367 Trivers's theory of parent-offspring conflict associated fauna and flora, biotic history of has shed relatively little empirical light on sib- Australia, possible feeding habits, and the like. licide in birds will undoubtedly provoke some The book's concept, organization, and visual raised eyebrows. But Mock's perspectives are so presentation are brilliant, but the execution has clearly articulated and thoughtfully explained some serious flaws. that even readers with dissenting views will be The first known species, Dromornis australis, unlikely to object strenuously. was described in 1874 by Richard Owen, and I highly recommend this book to anyone inter- for almost a century and a quarter the drom- ested in the evolutionary biology of family con- ornithids were associated with paleognathous flict. It will be especially useful to ornithologists ratites such as emus and cassowaries. The name working on such topics as hatching asynchrony "mihirung" was originally adopted for these siblicide, brood reduction, and parental care. birds by Rich (1979) from Aboriginal traditions And for anyone wanting to know how to write of giant emus (mihirung paringmal) believed pos- a scholarly biological book that will appeal to a sibly to apply to Genyornis. It was not until the general audience. More Than Kin and Less Than seminal paper of Murray and Megirian (1998), Kind should be essential reading.•RONALD L. based on newly collected Miocene skull mate- MUMME, Department of Biology, Allegheny College, rial, that the anseriform relationships of the 520 North Main Street, Meadville, Pennsylvania Dromornithidae were revealed. Six years later, 16335, USA. E-mail: [email protected] Murray and Vickers-Rich glibly and rather mis- leadingly refer to these birds as gigantic geese and imply that their nonratite nature should have been apparent earlier. E. C. Stirling and A. H. C. Zietz, who were director and assistant director, respectively, of the South Australian Museum, excavated and The Auk 122(1):367-371, 2005 published impressive monographs on extensive © The American Ornithologists' Union, 2005. fossil material of G. newtoni from 1896 to 1913. Printed in USA. According to Murray and Vickers-Rich, Stirling and Zietz's comparisons and Magnificent Mihirungs. The Colossal Flight- discussion of Genyornis morphology and less Birds of the Australian Dreamtime.•Peter relationships are so intently focused on F. Murray and Patricia Vickers-Rich. 2004. Indiana ratite osteology that as each structural University Press, Bloomington, Indiana, vii + 410 incongruity is realized they dutifully note pp. ISBN 0253342821. Quarter cloth and boards, it, adjust their spectacles, and move on as $75.00.•This is an exhaustive, superbly illus- though there were no alternatives, (p. 59) trated treatment of the Dromornithidae, a family of large to very large flightless birds known from Furthermore, the skull "contains ample evi- fossils from Australia and Tasmania. The fossils dence to have placed the Genyornis [sic] among range in age from a rather equivocal early Eocene the Neognathae even at the time Stirling partial footprint to the late Pleistocene Genyornis described it" (p. 60). The penetrating clarity of newtoni, which died out about 50,000-30,000 Vickers-Rich's hindsight is a scientific marvel, years ago, presumably as a result of human pré- for in her own monographic treatment of the dation and habitat modification by fire. Dromornithidae (Rich 1979) they were ratites The book is divided into four major sections: from start to finish. "Discovery," a short chapter on the history of For the record, the first person in the history fossil finds and their discoverers; "Systematics of the Dromornithidae to insist that these birds and Morphology," the longest section, con- could not be ratites was unlovable old cladist- taining paleontology, descriptive osteology, baiting moi (Olson 1985). This seemingly signifi- systematics and phylogeny, and evolutionary cant fact, acknowledged by Murray and Megirian origins; "Paleobiology," consisting of functional (1998), was omitted by Murray and Vickers-Rich. morphology, biomechanics, weight estimates, Although the reference can be found in the bibli- and so forth; and "Paleoecology," which treats ography, it is not cited in the text. 368 Reviews [Auk, Vol. 122 Although I was pleased to learn of the evi- lacking the hindlimbs, from the London Clay dence that the dromornithids were derived and was referred to the Anseranatidae on the from Anseriformes, one might now fairly ask basis of highly distinctive derived characters of "Derived how many times?" Nowhere here the pectoral girdle. The bill morphology indi- or in Rich (1979) is there a clearly articulated cates very clearly that it was a filter-feeder. The argument or character analysis demonstrat- type species of Anatalavis from marine deposits ing that the Dromornithidae constitute a in New Jersey is either late Cretaceous or earli- monophyletic group. The skull and foot struc- est Paleocene. Thus, the earliest certain member ture of the clade that includes Genyornis are of the Anseriformes, which is also the earliest very different from the skull and foot, when member of the Anseranatidae, was a filter- known, of the other members of the family. If feeder. This strongly suggests that the macro- all these birds are large flightless derivatives feeding Magpie Goose is secondarily derived of Anseriformes, why might not the Genyornis from a filter-feeder. Screamers, too, may thus clade have evolved large size and flightless- be so derived. ness independently within the Anseriformes? Unfortunately, the two known early Eocene In fact, because details of the skull of Genyornis taxa of Anhimidae, from Wyoming and are poorly known (owing to the incomplete, England, have never been described. Those crushed nature of the available specimens), the were not filter-feeders and lacked many of the evidence that the relationships of this group lie autapomorphic characters of modern scream- with the Anseriformes is less satisfactory than ers, such as great skeletal pneumaticity and in older taxa for which better skulls are known. the double-spurred carpometacarpus. Murray For example, the large, blade-like retro-articular and Vickers-Rich make a weak case for drom- process shown for Genyornis, one of the most ornithids being screamer-like, on the basis of characteristic features of the Anseriformes, the supposed lack of uncinate processes and appears to be an almost entirely hypothetical the presence of a knob at the distal end of the construct (fig. 107, p. 127). Monophyly of the pectoral crest of the humérus. Eocene scream- Dromornithidae is, therefore, an issue that still ers lack that knob, however. Furthermore, the needs to be addressed. authors show a rib of D. stirtoni (fig. 60) with a Given that the dromornithids, or at least some large, very distinct facet for an uncinate process. of them, belong in the Anseriformes, where do Such a facet would seem to indicate a synovial their relationships lie within the order? This joint, and 1 doubt that such would form were question gets more consideration than that of there not a bony uncinate process to articulate monophyly, but its treatment is badly distorted with it. by prejudices and by another, more serious, In the end, no good case is made for the omission of pertinent literature. relationships of the Dromornithidae within The authors are dismissive, even derisive, the Anseriformes, even at the level of family. of the suggestion of Olson and Feduccia (1980) Although the authors favor a closer relationship that screamers (Anhimidae) might be second- with either the Anhimidae or Anseranatidae, it arily derived macrofeeders that evolved from would seem that even the Anatidae, through a filter-feeding ancestor. They conclude that a terrestrial goose-like form such as Cereopsis, macrofeeders such as screamers and the Magpie cannot be ruled out. Goose (Anseranas semipalmata) represent the The generic-level systematics used in this primitive condition in Anseriformes and that book is a complete mess. To begin with, the filter feeding is derived. They also state that the type species of Dromornis, Owen's D. australis, Anseranatidae have no fossil record. Did they is known only from a single femur and remains simply overlook the early Eocene Anatalavis practically the only Pliocene fossil of the fam- oxfordi (Olson 1999)? That species was published ily. The paucity of Pliocene material makes it in one of the quadrennial proceedings of the uncertain that the late Miocene D. stirtoni is cor- Society of Avian Paleontology and Evolution, rectly referred to Dromornis. The close relation- each of which has become a primary source ship between the middle Miocene Bullockornis in avian paleontology and ought to be famil- planei and the larger D. stirtoni that succeeds iar to everyone in the field. Anatalavis oxfordi it is emphasized repeatedly. At first implicitly was based on an excellent associated skeleton. (p. 273), and then more explicitly (p. 330), it is January 2005] Reviews 369 suggested that this is an ancestral-descendent farrago of indecision before such an important relationship. Why, then, are the two species book was published. Still, because of the supe- maintained in separate genera? rior nature of the illustrations, it is possible for Then we have the species that was origi- an intelligent reader to make some sense of part nally described by Rich (1979) as Ilbandornis'? of the evolutionary history of these birds, in lawsoni. The only change in status for this spe- spite of the disastrous nomenclature. cies in 25 years is that quotation marks were A lengthy chapter on body mass estimates added around the genus, so that everywhere goes into great detail to document three dif- it appears as "Ilbandornis?" lawsoni. Do the ferent methods of estimating mass and rather quotation marks make the identity even more diffidently concludes that D. stirtoni may have uncertain than before, or make us more certain been the heaviest bird that ever lived.

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