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J A Kirsch

Publications and source records attributed to J A Kirsch.

At least 19 recordsLinked to original sources
PubMed1991

DNA hybridization evidence for the Australasian affinity of the American marsupial Dromiciops australis.

DNA hybridization was used to compare representatives of the major groups of marsupials and a eutherian outgroup. Because of the large genetic distances separating marsupial families, trees were calculated from normalized percentages of hybridization; thermal-melting statistics, however, gave identical topologies for the well-supported clades. The most notable results were the association of the only extant microbiotheriid, Dromiciops australis, an American marsupial, with the Australasian Diprotodontia, and of both together with the Dasyuridae. Estimates of the rate of divergence among marsupial genomes suggest that the Dromiciops-Diprotodontia split occurred approximately 50 million years ago, well after the establishment of the major clades of marsupials but before deep oceanic barriers prohibited dispersal among Australia, Antarctica, and South America. Because Dromiciops is nested within an Australasian group, it seems likely that dispersal from Australia accounts for its present distribution.

Animals↗
PubMed1990

DNA hybridization, cladistics, and the phylogeny of phalangerid marsupials.

Single-copy DNA/DNA hybridization experiments and numerical cladistic analyses of anatomical characters were used to investigate relationships among nine phalangerid (Marsupialia) species from four different genera. Both rate-dependent and rate-independent analyses of molecular data indicate that species of Trichosurus from one clade and that Strigocuscus, Phalanger, and Spilocuscus form a second. Within the latter group, Spilocuscus is excluded from a Strigocuscus-Phalanger clade, which, in turn, is not fully resolved on a jackknife strict consensus tree. Minimum-length Dollo, Wagner, and Camin-Sokal parisomy trees based on 35 anatomical characters, in contrast, suggest placement of Strigocuscus with Trichosurus rather than with Spilocuscus and Phalanger. However, there are two derived characters that support the alternative arrange of Strigocuscus with Spilocuscus and Phalanger and one character that further unites Strigocuscus and Phalanger. Thus, DNA hybridization results are not inconsistent with the distribution of derived character states among anatomical characters, only with minimum-length trees based on character data.

Animals↗
PubMed1990

DNA/DNA hybridization studies of the carnivorous marsupials. I: The intergeneric relationships of bandicoots (Marsupialia: Perameloidea).

A complete suite of comparisons among six bandicoot species and one outgroup marsupial was generated using the hydroxyapatite chromatography method of DNA/DNA hybridization; heterologous comparisons were also made with three other bandicoot taxa. Matrices of delta Tm's, delta modes, and delta T50Hs were generated and corrected for nonreciprocity, homoplasy, and, in the case of delta Tm's, normalized percent hybridization; these matrices were analyzed using the FITCH algorithm in Felsenstein's PHYLIP (version 3.1). Uncorrected and nonreciprocity-corrected matrices were also jackknifed and analyzed with FITCH to test for consistency. Finally, sample scores for delta Tm, delta mode, and delta T50H matrices were bootstrapped and then subjected to phylogenetic analysis. These manipulations were carried out, in part, to address criticisms of the statistics used to summarize DNA/DNA hybridization (especially T50H) and the method itself. However, with the exception of an unresolved trichotomy among the two Echymipera species and Peroryctes longicauda, all trees showed the same branchpoints. Except in the case of the tree generated from reciprocal-corrected delta Tm data, nodes were stable under jackknifing; and, again excepting the above-mentioned trichotomy, all nodes were supported by 95% or more of the bootstrapped trees. These results suggest that, despite arguments to the contrary, all three summary statistics can be valid for DNA/DNA hybridization data. Of taxonomic interest is the placement of Echymipera spp. and Peroryctes longicauda together and separate from the more distant Peroryctes raffrayanus; the genus Peroryctes is thus at least paraphyletic. The trees further grouped Echymipera-plus-Peroryctes as the sister group of Isoodon-plus-Perameles. Limited hybridizations with Macrotis lagotis suggest that its current position as representative of an entirely distinct family of perameloids is correct.

Animals↗
PubMed1989

Rates of single-copy DNA evolution in phalangeriform marsupials.

DNA/DNA hybridization was used to investigate the relationships of taxa representing the phalangeriform marsupial families Acrobatidae, Burramyidae, Macropodidae, Petauridae, Phalangeridae, and Pseudocheiridae and (as an outgroup) the bandicoot family Peramelidae. In the course of this, a marked rate slowdown was noted in the burramyid lineage represented by Cercartetus caudatus; ANOVA (with Tukey's test) and F-ratio tests of both corrected and uncorrected data matrices confirmed this rate disparity. As burramyids are small, short-generation-time phalangeriforms, these data present a striking counterexample to the common view that rates of change in DNA sequences are inversely correlated with generation time.

Analysis of Variance↗
PubMed1988

Conflict over the molecular clock.

Figure 3 (p. 1310) in the report "A 115-kD polypeptide immunologically related to erythrocyte band 3 is present in Golgi membranes" by S. Kellokumpu et al. (2 Dec., p. 1308) was incorrectly printed. The correct figure is reproduced below.

Animals↗
PubMed1984

Brain traits through phylogeny: evolution of neural characters.

We have previously derived a hypothetical tree of the lines of mammalian descent, based upon a comprehensive numerical taxonomic cross-analysis of primitive and derived states of 15 brain traits in 38 representative species. In this communication we use this tree to describe the probable sequence of changes that have taken place in phylogenetic history. 2 characters proved to be multiply convergent, occurring in parallel in several disparate lines of descent. The remaining 9 characters each appeared in ancestors of one or another of the lineages and characterize related progeny.

Animals↗
PubMed1983

Phylogeny through brain traits: trees generated by neural characters.

Phylogenetic trees were computed by the Wagner algorithm from data on up to 15 brain characters scored on 154 specimens of 134 mammalian species. Because the data were not complete on all specimens, only one tree, of 18 taxa, was generated on all 15 features; a tree of 99 species was computed from 10 characters, and trees of 38 species from 10 and 12. The 38-taxon trees were considered best because they preserved most completely the integrity of mammalian orders. All trees consistently separated the subclasses of mammals and suggested that rodents, insectivores, and the tree shrew were most derived on the basis of brain characters. The trees' shapes are sensitive to small alterations in character scorings, largely because of the relatively few characters available and small differences in the number of states among them.

Animals↗
PubMed1983

Phylogeny through brain traits: the mammalian family tree.

Wagner trees based on the analysis of 15 brain characters scored on 154 specimens of 134 mammalian species show consistent patterns of relationship among the taxa, i.e. (1) monotremes are the primitive complement of the group uniting marsupials and placentals; (2) among marsupials, diprotodont Australian forms are more derived; (3) placental mammals divide into two groups of orders, roughly the ferungulates (carnivores, ungulates, and subungulates) and the unguiculates-plus-gliroids (chiropterans, dermopterans, lagomorphs, rodents, primates, and insectivores including elephant shrews); (4) edentates sit at the base of or just before the placental dichotomy; (5) the tree shrew and tarsier show the same pattern of distribution of brain traits as some rodents, as do prosimians and New World monkeys.

Animals↗
PubMed1982

Phylogeny through brain traits: fifteen characters which adumbrate mammalian genealogy.

Fifteen characters of brain organization are identified for which primitive and derived states can be distinguished, and which are thus useful in reconstructing mammalian phylogeny. The states of the characters are numerically coded in sequence from most primitive to most derived, to facilitate reciprocal comparisons in comprehensive genealogical analyses. The characters include certain features of cerebral circulation, cytoarchitecture, fiber pathways, and sensory projections. Seven characters are shared with nonmammals, a fact which makes then particularly useful for establishing their primitive vs. derived states; the other eight characters are features peculiar to mammals. Ten characters provide impressive reinforcement for traditional major grouping of the species, while five provide bases for new ideas about mammalian relationships.

Animals↗
PubMed1982

Phylogeny through brain traits: the distribution of categorizing characters in contemporary mammals.

The varying states of 15 characters of the central neural organization are tabulated as they occur in each of 147 mammalian species. For each character and species, scores are entered designating the primitive or derived state of the character as it is observed in that species. This tabulation provides data in numerically ordered form for multiple analyses of possible phylogenetic relationships which take into account variations in several different characters simultaneously.

Animals↗
PubMed1980

Phylogeny through brain traits. Relation of lateral olfactory tract fibers to the accessory olfactory formation as a palimpsest of mammalian descent.

In mammals the fibers of the dorsal lateral olfactory tract either pass under the accessory olfactory formation, or they penetrate through it separating the internal granule cells from the output cells. The use of this trait as a phylogenetic indicator in 181 specimens representing 131 species of 16 orders yielded evidence for common ancestry of Insectivora, Chiroptera, Dermoptera, Rodentia, and Primates (including Tupaia), since all share the derived trait, their dorsal lateral olfactory tract fibers passing through the accessory olfactory formation. Carnivora (including Pinnipedia), Hyracoidea, Perissodactyla, and most Artiodactyla share the primitive condition (fibers passing under) with the one order of monotremes and three marsupial orders. The Edentata and Lagomorpha may be separate from the two major placental groups and from each other, or they may represent successive stages in the evolution of the derived state through progressive alterations in the relative chronology of development of olfactory system components, or one or both orders may occupy an ancestral position with respect to the dichotomy within placental mammals.

Animals↗