Context of diversification of the viviparous Gyrodactylidae (Platyhelminthes, Monogenoidea)

Using four criteria proposed a decade ago by Brooks & McLennan to identify a case of adaptive radiation indicates that the evolutionary history of the viviparous clade of the Gyrodactylidae is dominated by nonvicariant processes. The viviparous clade, with 446 species, has significantly more species than its sister clade (one species), and high species richness was shown to be an apomorphic trait of only the viviparous gyrodactylids within the Gyrodactylidae. Reconciliation of the phylogenetic tree of the viviparous Gyrodactylidae with that of its hosts showed a low probability for cospeciation suggesting that adaptive modes of speciation and not vicariance were predominant during the historical diversification of the clade. The proposed hypothesis suggests that the Gyrodactylidae originated on the South American continent about 60 Mya after geographical dispersal and host switching of its common ancestor to demersal freshwater catfishes by a marine ancestor. Development of hyperviviparity and the consequent loss of 'sticky' eggs in conjunction with other symplesiomorphic and apomorphic features allowed rapid diversification coupled with high dispersal to new host groups and geographical areas by viviparous members of the Gyrodactylidae.     

Non‐concordant phylogeographical patterns of three widely codistributed endemic Western Balkans lacertid lizards (Reptilia,Lacertidae) shaped by specific habitat requirements and different responses to Pleistocene climatic oscillations

The Balkan Peninsula is a hot spot for European herpetofaunal biodiversity and endemism. The rock climbing lizards Dalmatolacerta oxycephala and Dinarolacerta mosorensis and the ground‐dwelling Dalmatian wall lizard Podarcis melisellensis are endemic to the Western Balkans, and their ranges largely overlap. Here, we present a comparative phylogeographical study of these three species in the area of their codistribution in order to determine the level of concordance in their evolutionary patterns. Phylogenetic analyses were performed based on two mitochondrial genes (cytochrome b and 16S rRNA), and a molecular clock approach was used to date the most important events in their evolutionary histories. We also tested for correlations regarding genetic differentiation among populations and their geographical distances. For all three species, a significant correlation between genetic and geographical distances was found. Within D. oxycephala, two deeply separated clades (‘island’ and ‘mainland clade’), with further subdivision of the ‘mainland clade’ into two subclades (‘south‐eastern’ and ‘north‐western’), were found. High sequence divergences were observed between these groups. From our data, the time of separation of the two main clades of D. oxycephala can be estimated at about 5 mya and at about 0.8 mya for the two subclades of the mainland clade. Within D. mosorensis, coalescence time may be dated at about 1 mya, while D. mosorensis and D. montenegrina separated around 5 mya. The results imply the existence of complex palaeo‐biogeographical and geological factors that probably influenced the observed phylogeographical patterns in these lacertid species, and point to the presence of numerous glacial/interglacial refugia. Furthermore, the observed cryptic genetic diversity within the presently monotypic species D. oxycephala prompts for a revision of its taxonomic and conservation status.     

Evolutionary history of Gymnocarpos (Caryophyllaceae) in the arid regions from North Africa to Central Asia

Gymnocarpos has only about ten species distributed in the arid regions of Asia and Africa, but it exhibits a geographical disjunction between eastern Central Asia and western North Africa and Minor Asia. We sampled eight species of the genus and sequenced two chloroplast regions (rps16 and psbB–psbH), and the nuclear rDNA (ITS) to study the phylogeny and biogeography. The results of the phylogenetic analyses corroborated that Gymnocarpos is monophyletic, in the phylogenetic tree two well supported clades are recognized: clade 1 includes Gymnocarpos sclerocephalus and G. decandrus, mainly the North African group, whereas clade 2 comprises the remaining species, mainly in the Southern Arabian Peninsula. Molecular dating analysis revealed that the divergence age of Gymnocarpos was c. 31.33 Mya near the Eocene and Oligocene transition boundary, the initial diversification within Gymnocarpos dated to c. 6.69 Mya in the late Miocene, and the intraspecific diversification mostly occurred during the Quaternary climate oscillations. Ancestral area reconstruction suggested that the Southern Arabian Peninsula was the ancestral area for Gymnocarpos. Our conclusions revealed that the aridification since mid‐late Miocene significantly affected the diversification of the genus in these areas.     

Sorting out the Snakebirds: The species status,phylogeny, and biogeography of the Darters (Aves: Anhingidae)

Although the avian family Anhingidae is unequivocally monophyletic, the number and relationships of the component species within the single genus (Anhinga) have long remained unclear. Here, we use extensive mitochondrial and nuclear DNA sequence data (8,878 bp) to show that four species should be recognized. Our fully resolved and well‐supported tree shows that the American Anhinga (Anhinga anhinga) is sister to the three Old World species, with the Oriental (A. melanogaster) and African (A. rufa) Darters sister within the Old World clade, which also includes the Australian Darter (A. novaehollandiae). We estimate that the divergence between the New World and Old World branches occurred 19–22 mya, with the Australian Darter separating from its Old World congeners 14–16 mya and the Oriental and African species splitting ~10 mya. The genus is yet another example of osteological conservatism in the Suliformes, which is comparable to that shown by the cormorants and shags. Nevertheless, the relationships we infer are congruent with recent plumage studies and are biogeographically plausible. We suggest that further investigation of the variation within the African and Australian Darters would be of interest.     

Evolutionary divergence times in the Annonaceae: evidence of a late Miocene origin of Pseuduvaria in Sundaland with subsequent diversification in New Guinea

Background  

Phylogenetic analyses of the Annonaceae consistently identify four clades: a basal clade consisting of Anaxagorea, and a small 'ambavioid' clade that is sister to two main clades, the 'long branch clade' (LBC) and 'short branch clade' (SBC). Divergence times in the family have previously been estimated using non-parametric rate smoothing (NPRS) and penalized likelihood (PL). Here we use an uncorrelated lognormal (UCLD) relaxed molecular clock in BEAST to estimate diversification times of the main clades within the family with a focus on the Asian genus Pseuduvaria within the SBC. Two fossil calibration points are applied, including the first use of the recently discovered Annonaceae fossil Futabanthus. The taxonomy and morphology of Pseuduvaria have been well documented, although no previous dating or biogeographical studies have been undertaken. Ancestral areas at internal nodes within Pseuduvaria are determined using dispersal-vicariance analysis (DIVA) and weighted ancestral area analysis (WAAA).     

Timing of clade divergence and discordant estimates of genetic and morphological diversity in the Slender Madtom,Noturus exilis (Ictaluridae)

Phylogeographic relationships, the timing of clade diversification, and the potential for cryptic diversity in the Slender Madtom, Noturus exilis, was investigated using mitochondrial Cyt b, nuclear RAG2, shape analysis, and meristic and pigmentation data. Three well-supported and deeply divergent clades were recovered from analyses of genetic data: Little Red River (White River drainage) clade, Arkansas + Red River (Mississippi River) clade, and a large clade of populations from the rest of the range of the species. Recovered clades showed little to no diagnostic morphological differences, supporting previous hypotheses of morphological conservatism in catfishes, and indicating morphology may commonly underestimate diversity in this group of fishes. The Little Red River clade is the most distinct lineage of N. exilis with 11 POM pores (vs. 10 in other populations) and unique Cyt b haplotypes and RAG 2 alleles. However, treating it as a species separate from N. exilis would imply that the other major clades of N. exilis are more closely related to one another than they are to the Little Red River clade, which was not supported.The UCLN age estimate for Noturus was 23.9 mya (95% HPD: 13.49, 35.43), indicating a late Oligocene to early Miocene origin. The age of N. exilis was estimated as late Miocene at 9.7 mya (95% HPD: 5.32, 14.93). Diversification within the species spanned the late Miocene to mid-Pleistocene. The largest clade of N. exilis, which dates to the late Miocene, includes populations from the unglaciated Eastern and Interior Highlands as well as the previously glaciated Central Lowlands. Diversification of this clade coincides with a drastic drop in sea-level and diversification of other groups of Central Highlands fishes (Centrarchidae and Cyprinidae). Sub-clades dating to the Pleistocene show that northern populations occurring in previously glaciated regions resulted from dispersal from populations in the Ozarks up the Mississippi River following retreat of the Pleistocene glaciers. Pre-Pleistocene vicariance, such as drainage pattern changes of the Mississippi River, also played a prominent role in the history of the species. The incorporation of a temporal estimate of clade diversification revealed that in some instances, phylogeographic breaks shared with other aquatic species were best explained by different or persistent vicariant events through time, rather than a single shared event.     

Molecular evidence for long distance dispersal across the Southern Hemisphere in the Ganoderma applanatum-australe species complex (Basidiomycota)

We examined phylogeographic relationships in the cosmopolitan polypore fungus Ganoderma applanatum and allies, and conservatively infer a possible age of origin for these fungi. Results indicate that it is very unlikely that members of this species complex diversified before the break-up of Gondwana from Laurasia ca 120 M years ago, and also before the final separation of the Gondwanan landmasses from each other that was achieved about 66 M years ago. An earliest possible age of origin of 30 M years was estimated from nucleotide substitution rates in the 18S rDNA gene. Phylogenetic reconstruction of a worldwide sampling of ITS rDNA sequences reveals at least eight distinct clades that are strongly correlated with the geographic origin of the strains, and also correspond to mating groups. These include one Southern Hemisphere clade, one Southern Hemisphere–Eastern Asia clade, two temperate Northern Hemisphere clades, three Asian clades, and one neotropical clade. Geographically distant collections from the Southern Hemisphere shared identical ITS haplotypes, and an ITS recombinant was noted. Nested clade analysis of a parsimony network among isolates of the Southern Hemisphere clade indicated restricted gene flow with isolation-by-distance among the New Zealand, Australia–Tasmania, Chile–Argentine, and South Africa populations, suggesting episodic events of long-distance dispersal within the Southern Hemisphere. This study indicates that dispersal bias plays a more important role than generally admitted to explain the Southern Hemisphere distribution of many taxa, at least for saprobic fungi.     

Fossil Record and Age of the Asteridae

The Asteridae is a group of some 80,000 species of flowering plants characterized by their fused corollas and iridoid compounds. Recent phylogenetic analyses have helped delimit the group and have identified four main clades within it; Cornales, Ericales, Lamiids and Campanulids, with the last two collectively known as the Euasteridae. A search for the oldest fossils representing asterids yielded a total of 261 records. Each of these fossils was evaluated as to the reliability of its identification. The oldest accepted fossils for each clade were used to estimate minimum ages for the whole of the Asteridae. The results suggest that the Asteridae dates back to at least the Turonian, Late Cretaceous (89.3 mya) and that by the Late Santonian-Early Campanian (83.5 mya) its four main clades were already represented in the fossil record.     

Molecular phylogeny and intraspecific differentiation of the Eremias velox complex of the Iranian Plateau and Central Asia (Sauria,Lacertidae)

The Central Asian racerunner, Eremias velox, is a widely distributed lizard of the Eurasian lacertid genus Eremias. Nucleotide sequences of mitochondrial genes, cyt b and 12S rDNA from 13 geographically distant localities in Iran and Central Asia, were analysed. Phylogenetic analyses of the sequence data unambiguously recovered five major clades within the E. velox complex with a high level of genetic divergence, indicating long periods of isolation. The basal position of the Iranian clades in the phylogenetic trees suggests that the E. velox clade originated on the Iranian plateau in the Middle Miocene. According to our calibrations, the northern Iranian clade diverged first some 10–11 Ma and that the Central Asian lineages split from the northeastern Iranian lineage approximately 6 Ma, most likely as a result of uplifting of the Kopet‐Dagh Mountains in the northern margin of the Iranian plateau. Topology of the phylogenetic trees, combined with the degree of the genetic distances among the independent lineages recovered in this study, provide a solid foundation for a fundamental revision of the taxonomic status of the major clades within this species complex.     

Molecular phylogeny of the marine littoral genus Cafius (Coleoptera: Staphylinidae: Staphylininae) and implications for classification

Jeon, M.‐J., Song, J.‐H. & Ahn, K.‐J. (2012). Molecular phylogeny of the marine littoral genus Cafius (Coleoptera: Staphylinidae: Staphylininae) and implications for classification. —Zoologica Scripta, 41, 150–159. A phylogenetic analysis of the marine littoral genus Cafius Stephens is presented based on molecular characters. The data set comprised partial mitochondrial COI (910 bp), COII (369 bp), 12S rDNA (351–354 bp), 16S rDNA (505–509 bp) and nearly complete sequences of 18S rDNA (1814–1830 bp) for 37 species. Twenty‐seven Cafius species, representing five of six subgenera, two Remus Holme species, three Phucobius Sharp species, monotypic Thinocafius Steel and four outgroups were included. The sequences were analysed simultaneously by parsimony analysis in Tree Analysis Using New Technology (TNT) with traditional manual alignment, direct optimization (DO) in the program POY4 under a variety of gap costs and partitioned Bayesian analysis for the combined data. The genus Cafius and nearly all of its subgenera were not supported as being monophyletic. Instead, all analyses (parsimony trees, DO tree under equal weighting and Bayesian tree) showed monophyly of Cafius + Phucobius + Remus + Thinocafius (clade Z) and all seven nested clades (A–G). However, the phylogenetic relationships among clades A–G differed among the analyses. The genus Phucobius was recovered as a monophyletic group within Cafius. The genus Remus was not monophyletic but formed a clade with C. rufescens Sharp and C. rufifrons Bierig within Cafius. The genus Thinocafius formed a clade with C. caviceps Broun, C. litoreus (Broun) and C. quadriimpressus (White) within Cafius. We propose new concepts for the genus Cafius and its related genera, and the seven nested clades.     

Genetic differentiation of the pine processionary moth at the southern edge of its range: contrasting patterns between mitochondrial and nuclear markers

The pine processionary moth (Thaumetopoea pityocampa) is an important pest of coniferous forests at the southern edge of its range in Maghreb. Based on mitochondrial markers, a strong genetic differentiation was previously found in this species between western (pityocampa clade) and eastern Maghreb populations (ENA clade), with the contact zone between the clades located in Algeria. We focused on the moth range in Algeria, using both mitochondrial (a 648 bp fragment of the tRNA‐cox2) and nuclear (11 microsatellite loci) markers. A further analysis using a shorter mtDNA fragment and the same microsatellite loci was carried out on a transect in the contact zone between the mitochondrial clades. Mitochondrial diversity showed a strong geographical structure and a well‐defined contact zone between the two clades. In particular, in the pityocampa clade, two inner subclades were found whereas ENA did not show any further structure. Microsatellite analysis outlined a different pattern of differentiation, with two main groups not overlapping with the mitochondrial clades. The inconsistency between mitochondrial and nuclear markers is probably explained by sex‐biased dispersal and recent afforestation efforts that have bridged isolated populations.     

Intraspecific diversity and distribution of the cosmopolitan species Pseudo‐nitzschia pungens (Bacillariophyceae): morphology,genetics, and ecophysiology of the three clades

Three clades of Pseudo‐nitzschia pungens, determined by the internal transcribed space (ITS) region, are distributed throughout the world. We studied 15 P. pungens clones from various geographical locations and confirmed the existence of the three clades within P. pungens, based on ITS sequencing and described the three subgroups (IIIaa, IIIab, and IIIb) of clade III. Clade III (clade IIIaa) populations were reported for the first time in Korean coastal waters and the East China Sea. In morphometric analysis, we found the ultrastructural differences in the number of fibulae, striae, and poroids that separate the three clades. We carried out physiological tests on nine clones belonging to the three clades growing under various culture conditions. In temperature tests, only clade III clones could not grow at lower temperatures (10°C and 15°C), although clade I and II clones grew well. The estimated optimal growth range of clade I clones was wider than that of clades II and III. Clade II clones were considered to be adapted to lower temperatures and clade III to higher temperatures. In salinity tests, clade II and III clones did not grow well at a salinity of 40. Clade I clones were regarded as euryhaline and clade II and III clones were stenohaline. This supports the hypothesis that P. pungens clades have different ecophysiological characteristics based on their habitats. Our data show that physiological and morphological features are correlated with genetic intraspecific differentiation in P. pungens.     

Pleistocene speciation of freshwater crabs (Crustacea: Potamidae: Geothelphusa) from northern Taiwan and southern Ryukyus, as revealed by phylogenetic relationships

The phylogenetic relationship among freshwater crab species of Geothelphusa from northern Taiwan and the Yaeyama Group of islands (including Iriomote and Ishigaki) in the southern Ryukyus was studied using the mitochondrial genes 16S rRNA and COI. Our results support the hypothesis that speciation of Geothelphusa among these islands was the result of cyclic glaciations and interglaciations during the Pleistocene. Two main clades, one the Taiwan Group (containing several clades, including most Taiwanese Geothelphusa species except Geothelphusa miyazakii but including Geothelphusa minei from Yaeyama), was estimated to be separated from its sister group, the southern Ryukyus-northern Taiwan (SRN) clade (including G. miyazakii, Geothelphusa shokitai, Geothelphusa fulva and G. marginata from northern Taiwan, the Pinnacle Islands [=Diaoyutai Islands or Senkaku Islands] and Yaeyama) at about 5.3 million years ago (mya). G. shokitai was separated from others within the SRN clade at 2.4 mya, but was probably derived from G. miyazakii in northern Taiwan. The ancestor of G. miyazakii is hypothesised to have dispersed from ancestors in Yaeyama and then isolated at 2.0 mya during the Pleistocene interglaciations. This is similar to the speciation of G. minei in Yaeyama at 1.5 mya, except that its ancestors originated from north-eastern Taiwan. Four clades of freshwater crabs are present in the Fushan Botanical Garden, located in the mountainous area of north-eastern Taiwan, which might be due to the historical rearrangements of the drainage and proximity of the various river origins.     

Molecular patterns of differentiation in canyon treefrogs (Hyla arenicolor): evidence for introgressive hybridization with the Arizona treefrog (H. wrightorum) and correlations with advertisement call differences

Detection of genetic and behavioural diversity within morphologically similar species has led to the discovery of cryptic species complexes. We tested the hypothesis that US populations of the canyon treefrog (Hyla arenicolor) may consist of cryptic species by examining mate‐attraction signals among three divergent clades defined by mtDNA. Using a multi‐locus approach, we re‐analysed phylogenetic relationships among the three clades and a closely related, but morphologically and behaviourally dissimilar species, the Arizona treefrog (H. wrightorum). We found evidence for introgression of H. wrightorum’s mitochondrial genome into H. arenicolor. Additionally, the two‐clade topology based on nuclear data is more congruent with patterns of call variation than the three‐clade topology from the mitochondrial dataset. The magnitude of the call divergence is probably insufficient to promote isolation of the nuclear DNA‐defined clades should they become sympatric, but further divergence in call properties significant in species identification could promote speciation in the future.     

Macroevolutionary persistence of heritable endosymbionts: acquisition,retention and expression of adaptive phenotypes in Spiroplasma

The phylogenetic incongruence between insects and their facultative maternally transmitted endosymbionts indicates that these infections are generally short‐lived evolutionarily. Therefore, long‐term persistence of many endosymbionts must depend on their ability to colonize and spread within new host species. At least 17 species of Drosophila are infected with endosymbiotic Spiroplasma that have various phenotypic effects. We transinfected five strains of Spiroplasma from three divergent clades into Drosophila neotestacea to test their capacity to spread in a novel host. A strain that causes male killing in Drosophila melanogaster (its native host) also does so in D. neotestacea, even though these host species diverged 40–60 mya. A strain native to D. neotestacea (designated sNeo) and the two other strains of the poulsonii clade of Spiroplasma confer resistance to wasp parasitism, suggesting that this trait may be ancestral within this clade of Spiroplasma. Conversely, no strain other than sNeo conferred resistance to the sterilizing effects of nematode parasitism, suggesting that nematode resistance is a recently derived condition. The apparent addition of nematode resistance to a Spiroplasma lineage that already confers resistance to wasp parasitism suggests endosymbionts can increase the repertoire of traits conducive to their spread. The capacity of an endosymbiont to undergo maternal transmission and express adaptive phenotypes in novel hosts, without requiring a period of host–symbiont co‐evolution, enables the spread of such symbionts immediately after the colonization of a new host. This could be critical for the macroevolutionary persistence of facultative endosymbionts whose sojourn times within individual host species are relatively brief.     

Global mitochondrial DNA phylogeography and biogeographic history of the antitropically and longitudinally disjunct marine bryozoan Membranipora membranacea L. (Cheilostomata): another cryptic marine sibling species complex?

The origin of disjunct distributions in high dispersal marine taxa remains an important evolutionary question as it relates to the formation of new species in an environment where barriers to gene flow are not always obvious. To reconstruct the relationships and phylogeographic history of the antitropically and longitudinally disjunct bryozoan Membranipora membranacea populations were surveyed with mtDNA cytochrome oxidase 1 (COI) sequences across its cosmopolitan range. Maximum parsimony, maximum likelihood and Bayesian genealogies revealed three deep clades in the North Pacific and one monophyletic clade each in the southeast Pacific (Chile), southwest Pacific (Australia/New Zealand), North Atlantic and southeast Atlantic (South Africa). Human-mediated dispersal has not impacted M. membranacea’s large-scale genetic structure. M. membranacea did not participate in the trans-arctic interchange. Episodic long-distance dispersal, combined with climatic vicariance can explain the disjunct distribution. Dispersal led southward across the tropics perhaps 13 mya in the East Pacific and again northwards perhaps 6 mya in the Eastern Atlantic to colonize the North Atlantic from the south, and along the West Wind Drift to colonize Australia. The clades differentiated over evolutionary time in their respective ocean region, potentially forming a sibling species complex. The taxonomic status of the clades is discussed.     

A phylogenetic perspective on 160 years of troubled taxonomy of Niphargus (Crustacea: Amphipoda)

Niphargus is the largest genus of freshwater amphipods. Its systematics from the species to the family level has always been problematic. This study is the first comprehensive phylogenetic treatment of the chiefly subterranean group in 160 years of its taxonomic history. It includes 103 niphargid species plus outgroups, representing about one‐third of all nominal species. The samples originated mainly from type localities or adjacent sites and covered most of the morphological variability of the genus. Character sampling included nuclear 28S and mitochondrial 12S rDNA sequences, and 122 morphological characters. Quantitative morphological traits were coded using two alternative methods. The first one searches for gaps in the variability range of each character, while the second one uses absolute differences between the standardized raw data as weights. Different data sets yielded alternative topologies. All data support the monophyly of Niphargidae, while Niphargopsis— another niphargid genus — was consistently nested within Niphargus, loosing justification for its separate status. We predict a similar fate for all or most of the remaining six small niphargid genera, which were not yet scrutinized phylogenetically. Different topologies agreed in species composition of five large, well‐supported clades, although the hierarchic relationships between them remain unresolved. These clades reject all previously proposed taxonomic subdivisions of Niphargus, implying a high degree of morphological homoplasy that renders any morphology‐based groups questionable. The clade members are distributed within well‐established zoogeographical regions that do not exceed 1300 km across the longest diagonal. These results provide a framework for future studies on niphargid systematics, the evolution of endemism and cryptic diversity in subterranean environments, the mechanisms leading to exceptional morphological heterogeneity, historical biogeography, and applied ecological issues.     

Rapid diversification of Tragopogon and ecological associates in Eurasia

Tragopogon comprises approximately 150 described species distributed throughout Eurasia from Ireland and the UK to India and China with a few species in North Africa. Most of the species diversity is found in Eastern Europe to Western Asia. Previous phylogenetic analyses identified several major clades, generally corresponding to recognized taxonomic sections, although relationships both among these clades and among species within clades remain largely unresolved. These patterns are consistent with rapid diversification following the origin of Tragopogon, and this study addresses the timing and rate of diversification in Tragopogon. Using BEAST to simultaneously estimate a phylogeny and divergence times, we estimate the age of a major split and subsequent rapid divergence within Tragopogon to be ~2.6 Ma (and 1.7–5.4 Ma using various clock estimates). Based on the age estimates obtained with BEAST (HPD 1.7–5.4 Ma) for the origin of crown group Tragopogon and 200 estimated species (to accommodate a large number of cryptic species), the diversification rate of Tragopogon is approximately 0.84–2.71 species/Myr for the crown group, assuming low levels of extinction. This estimate is comparable in rate to a rapid Eurasian radiation in Dianthus (0.66–3.89 species/Myr), which occurs in the same or similar habitats. Using available data, we show that subclades of various plant taxa that occur in the same semi‐arid habitats of Eurasia also represent rapid radiations occurring during roughly the same window of time (1.7–5.4 Ma), suggesting similar causal events. However, not all species‐rich plant genera from the same habitats diverged at the same time, or at the same tempo. Radiations of several other clades in this same habitat (e.g. Campanula, Knautia, Scabiosa) occurred at earlier dates (45–4.28 Ma). Existing phylogenetic data and diversification estimates therefore indicate that, although some elements of these semi‐arid communities radiated during the Plio‐Pleistocene period, other clades sharing the same habitat appear to have diversified earlier.