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Gergen's (2009, 2011a, 2011b) relational approach and the participatory perspective (Westerman, 2005, 2006, 2014; Westerman & Steen, 2007) both subscribe to the view that we need to depart from treating the individual as the bounded, separate agent of the Cartesian framework. However, whereas Gergen's position moves away from individualistic accounts by holding that all psychological processes originate in relational processes in the dyad, the participatory perspective accomplishes this shift by viewing the person from the outset as a participant in the world of practical activities. In this article, I discuss implications that follow from this difference in starting points, including a number of ways in which the participatory perspective avoids problematic features of Gergen's approach. I argue that the participatory perspective offers a more sound framework for studying psychological phenomena, including interpersonal, or relational, processes themselves, the founding term of Gergen's relational approach. Regarding relational processes, it enables us to address questions about (a) continuity in interpersonal behavior across relationship contexts, and (b) how relational processes within a dyad change. I maintain that the limitations of Gergen's relational approach reflect the fact that it actually represents a variant of the Cartesian framework, even though Gergen's goal was to depart from that framework. In addition, I maintain that the participatory perspective provides a more adequate basis for work in the field because it successfully goes beyond Cartesianism.

Abstract: Complete nucleotide sequences of the cytochrome b and 12S rRNA genes and partial sequences of the mitochondrial 16S rRNA gene and the nuclear ɛ-globin gene were obtained from multiple exemplars of the New Guinean dasyurid, Myoictis. Allozyme data were also obtained from most of the same animals. The molecular data show that the genus comprises a number of genetically distinct lineages which correspond with groups proposed by Woolley (2005) on the basis of a number of morphological traits, including the form of the tail i.e. Myoictis leucura (sp. nov.), M. melas, M. wallacei and M. wavicus (new status). Divergence dates estimated from the weighted-average distances for the combined cytochrome b and 12S rRNA data, calibrated with a dasyurid-thylacine divergence 25 million years ago, suggest that the early cladogenic events separating Myoictis took place in the late Miocene. Subsequent separation of M. wavicus and M. leucura from a common ancestor as well as some genetic differentiation within M. melas, took place in the medial Pliocene.

Genetic variation within the Murina species group, which includes S. murina, S. gilberti, S. leucopus, S. dolichuraand S. archeri,was examined through analyses of complete 12S rRNA, partial control region mitochondrial DNA sequences and partial omega-globin nuclear DNA sequences. Sminthopsis butleriwas found to be an additional member of the Murina group, and appears to be most closely related to S. leucopusrather than the morphologically similar S. archeri. This latter species appears to be the most divergent member of the group, and there is a possible sister relationship between S. murinaand S. gilberti,as suggested by previous allozyme evidence. It appears that the systematic affinities of the taxonomically problematic northeastern Queensland populations of both S. murinaand S. leucopusand a disjunct population of S. gilberti(from the Western Australia/South Australia border) are indeed with those respective species; although each appears to belong to a distinct morphological and genetic lineage. A specimen of S. leucopusfrom Queensland was found to be as divergent from each of the southeastern Australian S. leucopussubspecies as they are from each other, suggesting that this northern population of S. leucopusmay also warrant recognition as a distinct taxon. Specimens of S. murina murinawere found to be genetically divergent from each other, and this subspecies appears to be paraphyletic, as suggested by previous morphological evidence.Genetic variation within the Murina species group, which includes S. murina, S. gilberti, S. leucopus, S. dolichuraand S. archeri,was examined through analyses of complete 12S rRNA, partial control region mitochondrial DNA sequences and partial omega-globin nuclear DNA sequences. Sminthopsis butleriwas found to be an additional member of the Murina group, and appears to be most closely related to S. leucopusrather than the morphologically similar S. archeri. This latter species appears to be the most divergent member of the group, and there is a possible sister relationship between S. murinaand S. gilberti,as suggested by previous allozyme evidence. It appears that the systematic affinities of the taxonomically problematic northeastern Queensland populations of both S. murinaand S. leucopusand a disjunct population of S. gilberti(from the Western Australia/South Australia border) are indeed with those respective species; although each appears to belong to a distinct morphological and genetic lineage. A specimen of S. leucopusfrom Queensland was found to be as divergent from each of the southeastern Australian S. leucopussubspecies as they are from each other, suggesting that this northern population of S. leucopusmay also warrant recognition as a distinct taxon. Specimens of S. murina murinawere found to be genetically divergent from each other, and this subspecies appears to be paraphyletic, as suggested by previous morphological evidence.

Most efforts to learn about interpersonal behavior reflect a shared set of key commitments. These commitments, in turn, reflect the Cartesian framework with its split between person and world. Guided by the recent work of certain developmental psychologists interested in social interaction (e.g., Fogel, 1993; Kaye, 1985) and by an alternative philosophical perspective that regards the person's involvement in practical activities as fundamental (Heidegger, 1962; Merleau-Ponty, 1962; Wittgenstein, 1958), the author maps out the participatory model of interpersonal behavior. According to this model, interpersonal behaviors are viewed as a person's contributions to doing something with other people. The author considers the model's implications for research by clinical psychologists on problematic behavior patterns in adults and psychotherapy process. The author also considers implications of rejecting the Cartesian framework for methodological concerns about the role of interpretation in research on interpersonal behavior.

Previous analyses of DNA sequences for mitochondrial cytochrome-b and 12S rRNA, along with the nuclear protamine P1 genes, suggested that the New Guinean dasyurid genera Phascolosorex and Neophascogale (phascolosoricines) form the sister groups of quolls (Dasyurus) and Tasmanian devils (Sarcophilus). This runs counter to a common perception that phascolosoricines are anatomically primitive and only distantly related to other dasyurids. We report the DNA sequences of two additional mitochondrial loci (tRNAVal and 16S rRNA) and nuclear loci (interphotoreceptor binding protein exon 1, beta-fibrinogen intron 7) from Phascolosorex dorsalis, Neophascogale lorentzii, and all but three other dasyurid species. These sequences, along with those previously published, comprise a dataset of 7053 nucleotides. Phylogenetic analyses indicate that phascolosoricines form a clade that is highly resolved as sister to Dasyurus + Sarcophilus. This result is obtained independently by mitochondrial and nuclear genes, and cannot be attributed to taxon- or gene-sampling bias, compositional heterogeneity, or the use of overly simplistic phylogenetic estimation procedures. A re-evaluation of published morphological data bearing on the relationships of phascolosoricines demonstrates that, although the conflict with molecular results is significant, it is limited to a small number of correlated dental features that show considerable homoplasy in their evolution.

The Australasian marsupial family Macropodidae includes potoroos and bettongs (Potoroinae) as well as larger kangaroos, wallabies, and pademelons (Macropodinae). Perhaps the most enigmatic macropodid is the banded hare wallaby, Lagostrophus fasciatus, a taxon listed as vulnerable by the IUCN. Lagostrophushad traditionally been grouped as a sister-taxon to hare wallabies (Lagorchestes), in a clade with hypsodont macropodines, or intercalated in some other fashion within Macropodinae. Flannery (1983, 1989) proposed a radically different hypothesis wherein Lagostrophusis outside of Macropodinae and is more closely related to extinct sthenurine (short-faced) kangaroos. Given this controversy, we addressed the phylogenetic placement of the banded hare wallaby using molecular sequences for three mitochondrial genes (12S rRNA, valine tRNA, 16S rRNA) and one nuclear gene (protamine P1). Diverse phylogenetic methods all provided robust support for a macropodine clade that excludes the banded hare wallaby. The split between macropodines and the banded hare wallaby was estimated at approximately 20 million years ago (mya) using the Thorne/Kishino relaxed molecular clock method. Whereas our molecular results neither corroborate nor refute the sthenurine hypothesis, since all short-faced kangaroos and their immediate ancestors are extinct, the overriding implication of molecular phylogenetic analyses is manifest: the banded hare wallaby is the only living relict of an ancient kangaroo lineage. Regardless of its precise relationships, special efforts should be directed at conserving this unique and endangered taxon, which has not been recorded from mainland Australia since 1906 and is now restricted to two tiny islands off the coast of Western Australia.

Genetic variation within the macroura species group, which includes Sminthopsis macroura, S. virginiae, S. douglasi, and S. bindi, was examined through analyses of complete mitochondrial 12S rRNA gene sequences, partial control-region DNA sequences, and allozymes. Divergent genetic lineages appear to be present within S. macrouraand S. virginiae, and it is likely that this genetic divergence equates to currently unrecognized taxonomic diversity. Specimens of S. macroura(as currently recognized) belong to three genetically distinct lineages that are highly divergent from one another. Two of these lineages may be synonymous with two previously recognized dunnart species—S. froggattiand S. stalkeri.The third appears to represent "true" S. macrouraand is itself genetically heterogeneous, with a number of subgroups present within it that may also represent currently unrecognized taxa. The mitochondrial DNA sequence divergences observed between S. virginiae nitelaand the two other S. virginiaesubspecies are equivalent to, or greater than, those noted between other dunnart species. Allozyme divergences between these subspecies were however slightly lower, and determination on whether S. virginiae nitelashould be returned to full species status (S. nitela) may require further evidence. Phylogenetic relationships between species in the macroura group appear to have been partially resolved, with individual 12S rRNA and combined mitochondrial DNA analyses recovering S. bindias the earliest diverging taxon. Other relationships between species in the group were either not consistently recovered or lacked strong support.

Dasyurid marsupials show a remarkable diversity of reproductive patterns ranging from aseasonal polyoestry to restricted annual breeding in which males synchronously die after a brief mating season. Previous studies have categorized dasyurid reproduction into six strategies, defined on the basis of five life-history characters. We provide an up-to-date summary of reproductive traits in dasyurid species and examine the evolution of these characters on a phylogeny for the family recently obtained from DNA sequence data. Our results suggest that reproductive evolution in modern dasyurids is characterized by a basal separation of subfamily lineages employing Strategy II (monoestrous females, restricted breeding season, 11 months to maturity; Dasyurinae) and Strategy V (polyoestrous females, extended breeding season, 8–11 months to maturity; Sminthopsinae). Strategies I (male die-off) and III (facultative polyoestry) appear to have arisen several times from Strategy II or V ancestors, and Strategy IV appears to have arisen within Sminthopsisfrom a Strategy V ancestor. Strategy VI (aseasonal breeding) has arisen independently in each of the four major dasyurid lineages (tribes), and is highly (but not perfectly) correlated with New Guinean endemism. This scenario is not strongly affected if reproductive characters are optimized on an alternative phylogeny more consistent with morphology-based opinions on species relationships. When evaluated in light of current habitat associations and geographic distributions, the reproductive data suggest that the Miocene diversification of modern dasyurids may have been correlated with the invasion of dry forest or woodland habitats.

Recent molecular studies have provided estimates of phylogeny for nearly all living and recently extinct species in the Order Dasyuromorphia, the dominant clade of insectivorous-carnivorous marsupials in Australasia. We review these studies along with morphology-based ones, and present an analysis of all cytochrome b, 12S rRNA, and protamine P1 gene sequences available. In light of these results, we provide a revised suprageneric classification and assess the implications of molecular and paleontological data for dasyurid cladogenesis. Molecular results divide extant dasyurids (Dasyuridae) into four major clades apart from the numbat (Myrmecobiidae) and thylacines (Thylacinidae). We recognize these clades as tribes Dasyurini (Dasyurus, Phascolosorex, and allied genera) and Phascogalini (Antechinus, Murexia, Phascogale) in the Subfamily Dasyurinae, and tribes Sminthopsini (Sminthopsis, Ningaui, Antechinomys) and Planigalini (Planigale) in the Subfamily Sminthopsinae. Each tribe shows a basal radiation of lineages corresponding to genera or species groups. Our results concur with the most recent previous synthesis of dasyurid phylogeny in many respects, but subsumption of New Guinean «phascolosoricines» and «muricines» within Dasyurini and Phascogalini, respectively, constitute significant differences. In particular, the sister-pairing of «phascolosoricines» with a Dasyurus–Sarcophilusclade implied by molecular data is difficult to reconcile with anatomy. Divergence rates of mitochondrial sequences are calibrated approximately by comparing thylacine-to-dasyurid distances with the age of the oldest thylacinid (Badjcinus, latest Oligocene). Estimated cladogenic dates suggest that extant subfamilies shared a common ancestor around 24 Mya and that major radiations began late in the mid-Miocene, consistent with the results of previous paleontological studies. The late-middle and late Miocene corresponds to an episode of faunal turnover in Australian marsupials (including the decline of thylacinid and bandicoot genera, as well as the rise of dasyurids) and to a time when uplift of the New Guinean highlands accelerated the transition from rainforest to drier habitats. Our findings are consistent with the hypothesis that continent-wide climate changes modulated macroevolution across these independent marsupial clades.

Although modern morphological and molecular analyses support the monophyly of the Australasian marsupial order Dasyuromorphia, there is much less certainty about relationships among its constituent families (Dasyuridae, Myrmecobiidae, and Thylacinidae). While most authors regard Dasyuridae as monophyletic, a few have suggested that thylacines, numbats, or both have their closest relatives among dasyurids. Recent morphocladistic studies have identified several basicranial characters as putative synapomorphies of dasyurids, but no features that clearly implicate thylacinids, myrmecobiids, or both, as the sister group of Dasyuridae. Only two previous DNA studies have included both thylacine and numbat sequences along with dasyurids, and neither provided strong resolution of interfamilial relationships. In this study, we report a more thorough analytical treatment of complete cytochrome b, 12S rRNA, and protamine P1 gene sequences from dasyuromorphians than has heretofore been attempted. Our results concur with previous morphological studies in showing that Dasyuridae is monophyletic and with immunological findings that thylacinids and dasyurids are sister groups, apart from myrmecobiids. However, the level of support for nodes is highly dependent on the method of phylogenetic analysis employed. Our results also suggest that partitioning of sequence data sets to account for substitutional heterogeneity within and among genes does not necessarily lead to a major reduction in the precision of estimated phylogenies.

Genetic variation within the genus Planigale was examined through analyses of 12S rRNA gene sequences and allozymes. The level of genetic divergence between the five currently recognised Planigale species was compared and the magnitude of divergence among populations assessed. This examination of molecular variation within the genus revealed that Planigale contains far more taxonomic diversity than is currently recognised. Specifically, the Pilbara region of Western Australia probably contains two currently unrecognised Planigale species and there is substantial genetic heterogeneity within the widespread species P. maculata. Ambiguity over the status of several genetic and/or morphological forms within the genus indicates that further taxonomic changes are likely to be warranted in the future. This study also demonstrates that the currently accepted geographic ranges of many planigale species require careful re-evaluation and that many specimens in collections are apparently misidentified. This is especially true of P. ingrami, which appears to have a much greater range than is currently recognised, being present in South Australia.

Alternative hypotheses in higher–level marsupial systematics have different implications for marsupial origins, character evolution, and biogeography. Resolving the position of the South American monito del monte (Order Microbiotheria) is of particular importance in that alternate hypotheses posit sister-group relationships between microbiotheres and taxa with disparate temporal and geographic distributions: pediomyids; didelphids; dasyuromorphians; diprotodontians; all other australidelphians; and all other marsupials. Among Australasian marsupials, the placement of bandicoots is critical; competing views associate bandicoots with particular Australasian taxa (diprotodontians, dasyuromorphians) or outside of a clade that includes all other Australasian forms and microbiotheres. Affinities of the marsupial mole are also unclear. The mole is placed in its own order (Notoryctemorphia) and sister–group relationships have been postulated between it and each of the other Australasian orders. We investigated relationships among marsupial orders by using a data set that included mitochondrial and nuclear genes. Phylogenetic analyses provide support for the association of microbiotheres with Australasian marsupials and an association of the marsupial mole with dasyuromorphs. Statistical tests reject the association of diprotodontians and bandicoots together as well as the monophyly of Australasian marsupials. The origin of the paraphyletic Australasian marsupial fauna may be accounted for by (i) multiple entries of australidelphians into Australia or (ii) bidirectional dispersal of australidelphians between Antarctica and Australia.

We report analyses of complete DNA sequences of the mitochondrial cytochrome b(1146 bp), 12S rRNA (974 bp), partial control region (371 bp) loci, and the nuclear protamine P1 (616 bp) gene from all but one species (Sminthopsis butleri) of the dasyurid marsupial tribe Sminthopsini, as well as several outgroups. Parsimony analyses of combined nuclear and mitochondrial data suggest that Antechinomysis sister to a clade consisting of Sminthopsisand Ningaui.Parsimony, maximum-likelihood, and mixed-model distance analyses consistently resolve several species groups within Sminthopsis.The Macroura group includes S. macroura, S. virginiae, S. douglasi,and S. bindi; S. butleriis also included here on the basis of partial 12S rRNA sequences. S. crassicaudatais resolved as sister to the Macroura clade. The Murina group includes S. murina, S. leucopus, S. gilberti, S. dolichura,and S. archeri. S. griseoventerand S. aitkeniare resolved as a clade, and there is moderate support for a group consisting of the genetically divergent species S. psammophila, S. hirtipes, S. youngsoni,and S. ooldea(possibly along with S. longicaudataand S. granulipes). Compositions of species groups are partially congruent with clades previously proposed on the basis of morphological data. Radiations within Sminthopsini appear to be coincident with major environmental changes since the mid-Miocene.

The basal split among living marsupials is traditionally placed between the cohorts Ameridelphiaand Australidelphia. Ameridelphia includes all American forms excepting the South AmericanDramicuipx gliroidex(Order Microbiotheria). Australidelphia includes all Australasian taxaplus Dromiciops glinmles. DNA data support Eometatheria Dromiciaps+ Diprotodontia +Dasyuromorphia + Notoryctemorphia) but do not resolve the position of bandicoots, whetherwith other australidelphians or with ameridelphians. Also, the most robust molecular trees (DNAhybridization, multigene studies) exhibit minimal branch subdivision and raise the possibility ofartit'actual associations owing to long branch attraction. We analyzed data sets that consistedof complete sequences tor four niitochondrial genes (cytochrome b, 12S rRNA, tRNA valine,16S rRNA). One data set included 14 marsupial taxa. A second data set included 14 marsupialsas well as outgroup sequences (one monolreme; 20 placentals). Phylogenetic analyses includedparsimony, minimum evolution, maximum likelihood, and quartet puzzling. When phylogeneticanalyses were restricted to just the marsupial sequences, there was 75 to 96% boostrap supportfor the separation of Ameridelphia versus Australidelphia. This suggests that either one orboth of these groups are monophyletic. Also, there was 71 to 98% bootstrap support for theseparation of Eometatheria versus Ameridelphia + Peramelina. Nonmonophyly of several a prioriclades was accepted by at least some statistical tests including the following: Diprotodontia+ Peramelina, Notoryctemorphia + Peramelina, Diprotodonlia + Notoryctemorphia, and themonophyly of Australasian marsupials. With the inclusion of outgroup sequences, there wasreduced bootstrap support for associations among marsupial orders and statistical tests failed toreject all interordinal associations that were tested.

The pig-footed bandicoot, Chaeropus ecaudatus, is presumed to be extinct as no specimens have been collected or seen since early this century. Usually classified as a specialized member of the family Peramelidae, there is nevertheless still some doubt as to its taxonomic affinities, because this animal is highly specialized and shows several uniquely derived characters. We report here the first attempt to determine the molecular relationships of this animal using mitochondrial 12S rRNA sequences derived from spirit-preserved museum specimens. Phylogenetic analysis shows that the sequence derived from the Chaeropussample is clearly that of a bandicoot. Within the bandicoot clade, the pig-footed bandicoot is quite distinct from all other taxa. Divergence-time estimates from the 12S rRNA sequences suggest that Chaeropusdiverged from the other bandicoot genera in the late Oligocene or early Miocene and that bandicoots diverged from other Australian families in the late Paleocene–early Eocene.

The fruit bat, Eonycteris spelaea, occurs from India through the Philippines to the southeast limit of its distribution in the Lesser Sunda islands of Indonesia. Mitochondrial DNA (mtDNA) variation was examined in Indonesian E. spelaeaisland populations by amplification of the D‐loop and digestion with restriction endonucleases. In addition, microgeographic variation was assessed by investigation of three cave populations within one island. A total of 24 genotypes, comprising two broad clades, was detected. The pattern of mtDNA variation reflects the colonization history of E. spelaeawith estimates of haplotype and sequence diversity highest in the older western populations and lowest at the eastern periphery of the species' distribution. These findings may also be associated with an environmental cline from west to east. There is also evidence that genetic distance between populations reflects geographic relationships, especially historical connectedness, as measured by Pleistocene sea‐crossing distances. At the microgeographic level, cave populations were heterogeneous and composed of diverse lineages suggesting restricted local interchange.

The fruit bat,Eonycteris spelaea, occurs from India through the Philippines to the southeast limit of its distribution in the Lesser Sunda islands of Indonesia. Mitochondrial DNA (mtDNA) variation was examined in IndonesianE. spelaeaisland populations by amplification of the D-loop and digestion with restriction endonucleases. In addition, microgeographic variation was assessed by investigation of three cave populations within one island. A total of 24 genotypes, comprising two broad clades, was detected. The pattern of mtDNA variation reflects the colonization history ofE. spelaeawith estimates of haplotype and sequence diversity highest in the older western populations and lowest at the eastern periphery of the species» distribution. These findings may also be associated with an environmental cline from west to east. There is also evidence that genetic distance between populations reflects geographic relationships, especially historical connectedness, as measured by Pleistocene sea-crossing distances. At the microgeographic level, cave populations were heterogeneous and composed of diverse lineages suggesting restricted local interchange.

The phylogenetic position of the recently extinct marsupial ‘wolf’, or thylacine (Thylacinus cynocephalus), has been a source of contention in mammalian systematics for nearly a century. Thylacines were endemic to Australia, but possessed striking anatomical similarities to Oligo–Miocene borhyaenid marsupials of adaptation to South America. At issue has been whether these features are indicative of common ancestry or convergent adaptation to carnivory. Recent morphological studies have supported both conclusions. Although current marsupial classifications group thylacines with Australian dasyuromorphians, this putative clade is characterized by mostly primitive morphological features. Attempts to determine thylacine affinities with ancient protein and DNA analyses have supported, but not resolved, a dasyuromorphian placement. We report 1546bp of mitochondrial DNA sequence (from cytochrome band 12S rRNA genes) and 841 bp of nuclear protamine gene sequence from the thylacine and representatives of all or most other marsupial orders. Phylogenetic analysis of these sequences shows unambiguously that thylacines are are members of Dasyuromorphia, and suggests a late Oligocene or very early Miocene divergence of familial lineages.

The interrelationships of the three mammalian groups, Monotremata, Marsupialia, and Eutheria, have been studied using DNA sequences from the mitochondrial 12S ribosomal RNA gene. The results suggest that the monotremes diverged from the living therians only shortly before eutherians and marsupials separated from each other, although there is some evidence for a slowdown in rate of base change in the monotreme lineage. Whtin the Monotremata, the two extant species of tachyglossids show a very close genetic relationship and the data suggest a very recent divergence. We have also confirmed that the Patagonian Monito del Monte,Dromiciops australis, is more closely related to the australidephian marsupials than it is to other South American species.

We report DNA sequence variation in 861 bp of the mitochondrial cytochromeb gene from 10 species of the dasyurid marsupial subfamily Phascogalinae (including the New Guinean genusMurexia) and an outgroup planigale (Planigale ingrami). Phylogenetic analyses of these sequences indicate that (1) the subfamily consists of three major clades corresponding to (a)Phascogale, (b) AustralianAntechinus, and (c) New Guinean “Antechinus” andMurexia; (2) “Antechinus” habbema constitutes the earliest branch of the New Guinean clade; and (3); “Antechinus” melanurus and “A.” naso are sister species within the New Guinean clade. Among Australian antechnuses,A. stuartii andA. swainsonii are more closely related to each other than either is toA. flavipes, a result that is seemingly at odds with all previous systematic studies. Although resolution is limited, it appears thatAntechnius andMurexia species form a clade to the exclusion ofPhascogale. This relationship suggests that male semelparity is not a strong synapomorphy for Australian antechinuses and phascogales, despite its apparent physiological similarity in the two groups.

Part of the mitochondrial 12S ribosomal RNA gene was amplified and sequenced for 26 marsupials. Multiple alignments for these sequences as well as seven additional sequences taken from GenBank were obtained using CLUSTAL. PAUP was used for phylogenetic analysis and to obtain random tree-length distributions. Analyses were performed with and without phylogenetic constraints. Our results clearly show that 12S rDNA contains phylogenetic signal at and above the ordinal level and is thus appropriate for addressing phylogenetic questions deep in the mammalian tree. Standard parsimony analyses provide some support for a clade containing diprotodontians, dasyurids,Dromiciops, andNotoryctes; transversion parsimony analysis suggests the possible inclusion of peramelids as well. Within the Diprotodontia, vombatids and phascolarctids cluster together on transversion parsimony and phalangerids may be associated with this clade. The enigmatic tarsipedids are apparently part of a clade that also contains pseudocheirids, petaurids, and acrobatids. The 12S sequences suggest that the origination of extant marsupial orders peaked 15 million years later than the equivalent taxonomic diversification of extant placental orders and may be entirely post-Cretaceous. Families of diprotodontian marsupials originated during the Eocene and early Oligocene, which is consistent with previous single-copy DNA hybridization results.

Archer provided the most recent and comprehensive suprageneric classification of dasyurid marsupials. Five extant subfamilies, two with constituent tribes, were recognized on the basis of morphological, serological, and allozyme data. Phylogenetic relationships among these groups, however, were totally unresolved. Subsequent molecular studies suggested that the endemic New Guinean subfamilies Muricinae and Phascolosoricinae are parts of larger Australian clades. Our objective in this study was to test the monophyly of Archer's seven groups and estimate relationships among them using DNA sequences from the mitochondrial cytochromeb (cyt-b) gene. We report 657 bp ofcyt-b from 32 dasyuroid species. Phylogenetic analysis of these data leads to the following conclusions: (1) muricines form a clade within Phascogalinae that includes endemic New GuineanAntechinus species; (2) the two genera of Phascolosoricinae are part of a more inclusive Dasyurinae; (3) Sminthopsinae is monophyletic, but the tribes Sminthopsini and Planigalini are not; and (4) the dasyurine tribes Dasyurini and Parantechini are probably not monophyletic. Relationships among Sminthopsinae, Dasyurinae (including phascolosoricines), and Phascogalinae (including muricines) remain unresolved.

We report the complete DNA sequences of the protamine P1 gene and flanking regions for 13 species of the marsupial family Dasyuridae. The structure of the protamine locus is conserved in dasyurids and consists of two exons (of lengths 142–151 and 47 bp) separated by an intron (208–240 bp). A key feature of the dasyund intron is a 38–40 by duplication found in all species examined to date. This duplication apparently predates the radiation of modern dasyurid lineages and may be homologous to a similar feature in the marsupial mole (Notoryctes). Sequences from a species of Planigale demonstrate that this genus is unique among marsupials in possessing cysteine residues in its protamine P1 molecules. Cysteines may provide enhanced chemical stability for condensed sperm nuclei, a physiological feature that would converge on the common eutherian pattern. Phylogenetic analysis of the protamine genes yields a tree that is largely congruent with previous molecular systematic studies in two areas: (1) There are three main dasyurid lineages corresponding to the Sminthopsinae, Dasyurinae, and Phascogalinae; (2) Dasyurinae and Phascogalinae are sister groups. This study is the first estimate of dasyurid relationships based on a nuclear DNA sequence.

We report sequences of the mitochondrial cytochromeb(1146 bp) and 12S rRNA (961 bp) genes, as well as the nuclear protamine P1 (608 bp) gene, from 13 species representing all four genera of the dasyurid marsupial subfamily Sminthopsinae. Mitochondrial sequences are partitioned into five categories (three codon positions in cytochromeb, and stems and loops in 12S rRNA) with distinct substitution rates, transition biases, and base compositions. We extract estimates of these biases from the sequences and employ them to calculate two overall distances based on the DNAML model. Phylogenetic analyses using distance and parsimony methods yield trees with different topologies for mtDNA and protamine. These trees are compatible with respect to highly resolved nodes, but incompatible with respect to length differences in a parsimony framework. The tree from combined-data analysis is dominated by the larger data set (mtDNA). The balance of evidence favors a basal separation ofPlanigalefrom other sminthopsines. WithinPlanigale, Pl. maculatais sister to the remaining species. Although the precise intergeneric affinities ofAntechinomysare unresolved,A. lanigerdoes not appear to be part of the genusSminthopsisas suggested by morphological data. The 12S rRNA resolvesNingaui rideiandN. yvonnaeas sister species.

The amino acid sequences of the α-lactalbumins of the echidna, Tachyglossus aculeatus, and the platypus, Ornithorhynchus anatinus, were compared with each other and with those of 13 eutherian and 3 marsupial species. Phylogenetic parsimony analyses, in which selected mammalian lysozymes were used as outgroups, yielded trees whose consensus indicated that the two monotremes are sister taxa to marsupials and eutherians and that the latter two clades are each other's closest relatives. The data do not support the notion of a Marsupionta (monotreme–marsupial) clade. Pairwise comparison between the α-lactalbumins yielded maximum-likelihood distances from which divergence dates were estimated on the basis of three calibration points. The distance data support the view that the echidna and platypus lineages diverged from their last common ancestor at least 50 to 57 Ma (million years ago) and that monotremes diverged from marsupials and eutherian mammals about 163 to 186 Ma.

We report complete sequences of the cytochrome b, 12S rRNA, and protamine P1 genes from 18 of the 21 extant species of dasyurine marsupials (family Dasyuridae). Partial sequences are included for Pseudantechinus ningbing, but no data are available for Ps. mimulusor Phascolosorex doriae. Phylogenetic analyses of these sequences yield compatible gene trees with limited resolution. Simultaneous parsimony analysis of all three genes suggests the following: (a) a basal polytomy of eight lineages; (b) a sister-group relationship between “phascolosoricine” genera (Neophascogaleand Phascolosorex, which are monophyletic) and Dasyums+ Sarcophilus; (c) monophyly of Dasyurus viverrinus, D. albopunctatus, D. geoffroii, and D. spartacusapart from other quolls and Sarcophilus; and (d) sister-pairing of D. geoffroiiand D. spartacusPrevious attempts at unraveling the phylogenetic history of dasyurines have produced strikingly inconsistent results, due in part to differences in character systems examined, interpretations of character homology and independence, and analytical methods employed. We provide some evidence that the basal polytomy is the result of rapid cladogenesis and suggest that this episode of dasyurine evolution is temporally correlated with the onset of aridification following the New Guinean uplift of 15 million years ago.

Controversy over the taxonomic designations within the genus Potoroushas highlighted problems associated with using only morphological data. The recent rediscovery of Gilbert's Potoroo has allowed us to reexamine the relationship of this species to other extant potoroos. Phylogenetic relationships and estimated divergence times are presented, based on electrophoretic and cytochrome bsequence data. There was considerable concordance between the data sets. We conclude that Gilbert's Potoroo is a separate species and should be referred to by its original name, Potorous gilbertii(Gould 1841). Estimates for potoroid divergences are in line with those of Flannery (1989).

Abstract.: The phylogenetic relationship among primates, ferungulates (artiodactyls + cetaceans + perissodactyls + carnivores), and rodents was examined using proteins encoded by the H strand of mtDNA, with marsupials and monotremes as the outgroup. Trees estimated from individual proteins were compared in detail with the tree estimated from all 12 proteins (either concatenated or summing up log-likelihood scores for each gene). Although the overall evidence strongly suggests ((primates, ferungulates), rodents), the ND1 data clearly support another tree, ((primates, rodents), ferungulates). To clarify whether this contradiction is due to (1) a stochastic (sampling) error; (2) minor model-based errors (e.g., ignoring site rate variability), or (3) convergent and parallel evolution (specifically between either primates and rodents or ferungulates and the outgroup), the ND1 genes from many additional species of primates, rodents, other eutherian orders, and the outgroup (marsupials + monotremes) were sequenced. The phylogenetic analyses were extensive and aimed to eliminate the following artifacts as possible causes of the aberrant result: base composition biases, unequal site substitution rates, or the cumulative effects of both. Neither more sophisticated evolutionary analyses nor the addition of species changed the previous conclusion. That is, the statistical support for grouping rodents and primates to the exclusion of all other taxa fluctuates upward or downward in quite a tight range centered near 95% confidence. These results and a site-by-site examination of the sequences clearly suggest that convergent or parallel evolution has occurred in ND1 between primates and rodents and/or between ferungulates and the outgroup. While the primate/rodent grouping is strange, ND1 also throws some interesting light on the relationships of some eutherian orders, marsupials, and montremes. In these parts of the tree, ND1 shows no apparent tendency for unexplained convergences.

This study investigated the relationship between complex grammatical structures and complex action sequences. A developmental progression of strategies for combining seriated cups identified in an earlier study (Greenfieldet al., 1972) was used to demonstrate some psychological consequences of formal parallels between language and action. The role of grammatical complexity and situational structure in language-action relations was explored. The results have implications for understanding the organization and development of complex action, its control by verbal commands, and the basic processes of speech comprehension.

Among the 19 currently recognized species of Sminthopsis, differences in the morphology of the free portion of the penis can be seen in the tip, which may be bifid, blunt, knoblike, or have a terminal median process, and which may have a subterminal skin fold; and the urethral opening and terminal passage (urethral grooves or urethral chamber). The urethra may open dorsally or ventrally, and the urethral grooves may lie mesially or ventrally on the bifid portion of the tip. Ten forms can be recognized and interspecific affinities based on penis morphology have been examined for congruence with species groupings based on other independent character sets including external, cranial, and dental characters and molecular data. Penis forms showed the greatest congruence with phylogenetic groups delineated by molecular data.

Five species of dasyurid marsupials endemic to New Guinea and herein referred to as Murexia longicaudata, M. rothschildi, M. habbema, M. naso, and M. melanurus have a varied taxonomic history. Until 1984, the latter 3 species had been assigned to the otherwise strictly Australian genus Antechinus, but comparisons of phallic morphology showed that this arrangement was untenable. Immunological and DNA hybridization studies of dasyurids suggested that New Guinean “antechinuses” were part of a clade that included M. longicaudata and M. rothschildi, a finding that was confirmed by early DNA sequence comparisons. Comprehensive analyses of cytochrome b, 12S rRNA, and protamine P1 sequences from all recognized dasyurid species led to the recommendation that these 5 species be included in a single genus (Murexia) that, along with Phascogale and Antechinus, constitutes the dasyurid tribe Phascogalini. Recently, however, a morphocladistic study concluded that these species are neither closely related to one another nor to any other dasyurid clade, placing them instead as successive basal branches within the family and assigning each to a distinct genus. Here we report results from an expanded DNA sequence data set that includes 2 additional mitochondrial loci (16S rRNA and control region) and 2 nuclear loci (beta-fibrinogen intron 7 and interphotoreceptor retinoid-binding protein exon 1) from phascogalin species and selected dasyurid and myrmecobiid outgroups. Phylogenetic analyses of these sequences show strong support for the monophyly of Murexia and its placement within Phascogalini, and provide the 1st resolved phylogeny of Murexia and Antechinus species. Reassessment of the morphological data suggests that the apparently primitive cranidental anatomy of Murexia may be an artifact of character polarizations or indicative of extreme homoplasy.

Phylogenetic analysis of complete cytochrome-b, 12S-rRNA, and protamine-Pl gene sequences from 17 of the 18 extant species of Phascogalinae (Marsupialia: Dasyuridae) suggests relationships that are strikingly congruent with previous morphological and molecular studies. Australian and New Guinean members of Antechinus comprise separate monophyletic groups, and the latter includes both species of the New Guinean genus Murexia. Among Australian species, two clades are recovered with high resolution: A. swainsonii and A. minimus; A. leo, A. bellus, and A. flavipes. Affinities of A. stuartii, A. godmani, and the agile antechinus are not resolved.

Phylogenetic analysis of the mitochondrial cytochrome-b gene from all species of the dasyurid marsupial genus Planigale reveals several key differences with morphology-based estimates of relationship. Planigale maculata is the most divergent member of the genus, possibly forming a separate clade with Sminthopsis. Planigale ingrami, Planigale gilesi, and Planigale novaeguinea form a clade in which the latter two are probably sister species. The position of Planigale tenuirostris is less well resolved, but it appears to be related to the P. ingrami clade. Cytochrome-b sequences from two specimens collected in the Pilbara region of western Australia are highly divergent from other planigales and from each other and may represent previously unrecognized species.