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1.
This paper reports the breeding biology and nesting seasons of the gadfly petrels which nest on the four islands of the Pitcairn group, Pitcairn, Henderson, Oeno and Ducie. The species currently breeding are Murphy's petrel Pterodroma ultima , Kermadec petrel P. neglecta , Herald petrel P. heraldica and Henderson petrel P. atrata. Of these, Murphy's petrel is the most numerous; an estimated 250000 pairs bred on Ducie, which is probably the major breeding station of the species. Novel basic breeding data for Murphy's petrel are presented. Incubation spells, averaging 19.3 days, are exceptionally long for a petrel. Phoenix petrel P. alba appears to have ceased to breed on the Pitcairn Islands since the 1922 surveys of the Whitney Expedition. Nesting success was low on Henderson Island during the study. For all four breeding species, less than 20% of eggs laid yielded fledglings. Failure occurred at the early chick stage and observations indicated that it was due to predation by Pacific rats Rattus exulans. Although rats are present on Ducie, predation was apparently less severe there. The situation on Oeno may be intermediate. I consider how the populations of Henderson are maintained in the face of this intense predation. The Murphy's petrel population may be sustained by immigration from Ducie while the Herald and Henderson petrel populations could be undergoing a long-term decline on Henderson. It is not clear how the Kermadec petrel population is maintained. The conservation implications of these findings are discussed.  相似文献   

2.
The Chatham petrel (Pterodroma axillaris) is an endangered species restricted to a single population on South East Island, Chatham Islands, New Zealand. The key threat to Chatham petrel breeding success is interference with chicks by broad-billed prions (Pachyptila vittata) prospecting for burrows for their oncoming breeding season. This burrow competition has resulted from alteration to breeding habitat by humans throughout the Chatham Islands. Understanding habitat preferences may enable managers to manipulate habitat to reduce burrow competition and will be essential in order to translocate Chatham petrels to a proposed second colony. Habitat characteristics surrounding both Chatham petrel and broad-billed prion burrows were quantified and selection ratios compared. Both Chatham petrels and broad-billed prions selected habitat factors associated with mature forest. Chatham petrels avoided a large number of habitat characteristics, which suggests they were habitat specific, and their preferred habitat is now limited. Broad- billed prions used a wide range of habitat characteristics, which suggests they are not habitat specific. This study recommends that selection values be used when deciding on the best location to establish a second Chatham petrel colony.  相似文献   

3.
Excluding the gadfly petrels Pterodroma spp. and the resident landbirds, this paper details the present status of bird species seen during an expedition to the Pitcairn Islands (Ducie, Henderson, Oeno and Pitcairn) in 1991 and early 1992. Ten species were recorded in the Islands for the first time. Several Southern Ocean petrels were recorded, most in the midwinter period of June and July. The populations of Christmas Island shearwaters breeding on Oeno and Ducie laid in synchrony every 9–10 months. The species is one of few with such a sub-annual, synchronized regime. The majority of other seabirds had an annual breeding cycle, laying between May and October. Around one percent of the world population of the bristle-thighed curlew passes the non-breeding season in the Pitcairn Islands.  相似文献   

4.
The Chatham petrel (Pterodroma axillaris) is an endangered species, restricted to a single population on South East Island, Chatham Islands. The key threat to breeding success is loss of chicks as a result of interference by broad-billed prions (Pachyptila vittata) prospecting for burrows for their oncoming breeding season. The effectiveness in decreasing interference using an artificial burrow entrance flap was investigated. The flap exploits behavioural differences between the species. Chatham petrels have a high incentive to push through a flap due to their investment in their burrow and chick, while prospecting prions are influenced by ease of access when searching for potential burrows. This trial found 90% of Chatham petrels entered their burrows through the artificial flap. Flaps acted as barriers to broad-billed prions, where 22% entered the burrow through the flap (P <0.01) compared to the control burrows. Artificial burrow flaps have the potential to provide a low cost, low labour strategy for protecting the known breeding population of Chatham petrels.  相似文献   

5.
Macaronesia (north‐east Atlantic archipelagos) has been host to complex patterns of colonization and differentiation in many groups of organisms including seabirds such as gadfly petrels (genus Pterodroma). Considering the subspecies of widely distributed soft‐plumaged petrel for many years, the taxonomic status of the three gadfly petrel taxa breeding in Macaronesia is not yet settled, some authors advocating the presence of three, two or one species. These birds have already been the subject of genetic studies with only one mtDNA gene and relatively modest sample sizes. In this study, using a total of five genes (two mitochondrial genes and three nuclear introns), we investigated the population and phylogeographical histories of petrel populations breeding on Madeira and Cape Verde archipelagos. Despite confirming complete lineage sorting with mtDNA, analyses with nucDNA failed to reveal any population structuring and Isolation with Migration analysis revealed the absence of gene flow during the differentiation process of these populations. It appears that the three populations diverged in the late Pleistocene in the last 150 000 years, that is 10 times more recently than previous estimates based solely on one mtDNA gene. Finally, our results suggest that the Madeira petrel population is ancestral rather than that from Cape Verde. This study strongly advocates the use of nuclear loci in addition to mtDNA in demographical and phylogeographical history studies.  相似文献   

6.
Aim  It is well established that many groups of plants and animals have undergone long-distance dispersal, but the extent to which this continues beyond initial colonization is largely unknown. To provide further insight into the frequency of gene flow mediated by long-distance dispersal, we investigated the origins of the fern Asplenium hookerianum on the Chatham Islands, and present a review of the contribution of molecular data to elucidating the origins of this archipelago's biota.
Location  Chatham Islands and New Zealand. A. hookerianum is scarce on the Chatham Islands but common in New Zealand, some 800 km to the west.
Methods  We compared chloroplast trnL–trnF DNA sequence data from Chatham Islands' A. hookerianum with extensive phylogeographic data for this genetically variable species in mainland New Zealand.
Results  Our sequencing revealed the presence of two haplotypes in Chatham Islands' A. hookerianum . These haplotypes differed by four mutational events and were each more closely related to haplotypes found in New Zealand than to each other.
Main conclusions  Despite the rarity of A. hookerianum on the Chatham Islands, its populations there appear to derive from at least two long-distance dispersal events from New Zealand, these possibly originating from different areas. We suggest that long-distance transoceanic dispersal, and the gene flow it can mediate, may be more common than is generally appreciated.  相似文献   

7.
VINCENT BRETAGNOLLE 《Ibis》1995,137(2):207-218
The taxonomic status of the populations of the polytypic Soft-plumaged Petrel Pterodroma mollis is controversial. Previous taxonomic studies used morphological characters (measurements and colouration) and univariate statistics. In this study, I add the use of multivariate statistics on morphological (biometry and colouration) and behavioural characters (vocalizations) of the petrels. Vocalizations are especially relevant in nocturnal burrowing petrels (such as the Soft-plumaged Petrel) and act as behavioural isolating mechanisms. The analysis, based on 535 calls from seven of the 11 known breeding localities of the species, showed that physical parameters of the call did not overlap at all between breeding localities in the northern and southern hemispheres but did so within each hemisphere. Conversely, the morphological analysis, based on morphometries from ten localities, displayed wide and significant intra-hemisphere variation, whereas there was no consistent difference between northern and southern parts of the breeding range. Thus analysis of the two sets of characters gave contradictory results. Calls, owing to their role in species-specific recognition in these birds, should be given priority over other characters for species separation. I suggest that only two species should be recognized, Pterodroma mollis and Pterodroma feae, with three subspecies each. I also examined behavioural affinities between P. mollislfeae groups and other gadfly petrels and found that P. mollis/feae were closest to Pterodroma cahow, whilst Pterodroma hasitata on the one hand and Pterodroma phaeopygia and Pterodroma externa (which may comprise two species instead of one) on the other belong to other groups of gadfly petrels.  相似文献   

8.
RICHARD ZOTIER 《Ibis》1990,132(4):525-534
The breeding season of the White-headed Petrel Pterodroma lessoni on Mayes Island off the Kerguelen archipelago was studied between December 1985 and February 1987. The birds returned to land in November, and the chicks hatched at the end of January and fledged in May. These incubation and fledging periods are among the longest known in the family Procellariidae. Successful birds normally bred every two years, which has not previously been reported for any member of this family. The breeding ecology is compared to that of other gadfly petrels from sub-antarctic and tropical waters, and the breeding frequency is discussed.  相似文献   

9.
Historical records suggest that the petrels of Round Island (near Mauritius, Indian Ocean) represent a recent, long‐distance colonization by species originating from the Atlantic and Pacific Oceans. The majority of petrels on Round Island appear most similar to Pterodroma arminjoniana, a species whose only other breeding locality is Trindade Island in the South Atlantic. Using nine microsatellite loci, patterns of genetic differentiation in petrels from Round and Trindade Islands were analysed. The two populations exhibit low but significant levels of differentiation in allele frequencies and estimates of migration rate between islands using genetic data are also low, supporting the hypothesis that these populations have recently separated but are now isolated from one another. A second population of petrels, most similar in appearance to the Pacific species P. neglecta, is also present on Round Island and observations suggest that the two petrel species are hybridizing. Vocalizations recorded on the island also suggest that hybrid birds may be present within the population. Data from microsatellite genotypes support this hypothesis and indicate that there may have been many generations of hybridization and back‐crossing between P. arminjoniana and P. neglecta on Round Island. Our results provide an insight into the processes of dispersal and the consequences of secondary contact in Procellariiformes.  相似文献   

10.
M. J. IMBER 《Ibis》1985,127(2):197-229
Taxonomic characters of gadfly petrels (Procellariidae: Pterodroma spp.) are reviewed and the genus is redefined. The structure of the upper intestines, which have become helicoidally twisted to varying degrees in most species, is an important character not hitherto used. Results of a phylogenetic study of the genus based mainly on the development of helicoidal intestines agree substantially with findings from studies of the Mallophaga parasitizing these petrels. One species, the Kerguelen Petrel Lugensa brevirostris, previously classified in Pterodroma, is shown to have closer affinity with some fulmar genera. The Tahiti Petrel Pseudobulweria rostrata and its rare or extinct relatives, formerly placed in a superspecies of Pterodroma, are more closely related to the Procellaria and Bulweria petrels, and may be derived from the link between the subfamilies Procellariinae and Fulmarinae. From consideration of the fossil record, anatomical characters and Mallophaga, a phylogeny of the Procellariidae is proposed which supports its monophyletic origin. Gadfly petrels apparently descended from the fulmars through the ancestral lines of Snow Petrels Pagodroma, the Kerguelen Petrel and finally the Blue Petrel Halobaena, which may have given rise separately both to gadfly petrels and to the prions Pachyptila. A late Pliocene origin of Pterodroma in the vicinity of southern New Zealand is possible. The genus Pterodroma is divided into four subgenera, representing four connected radiations, and 29 species are recognised. In probable chronological order, Proaestrelata (new subgenus) contains five species and is restricted to the Pacific Ocean, Cookilaria comprises six species restricted as breeders to the South Pacific, Hallstroma has seven species mainly in the tropics of the Pacific, Indian and South Atlantic Oceans, whereas Pterodroma includes 11 species which extend as breeders from the southwest Pacific west to the South Atlantic and into the North Atlantic. Ecological, physical and physiological adaptations in the evolution of gadfly petrels are discussed.  相似文献   

11.
MARK BOLTON 《Ibis》2007,149(2):255-263
A number of lines of evidence suggest that temporally segregated sympatric populations of Madeiran Storm‐petrels Oceanodroma castro breeding in the Azores are reproductively isolated and morphologically and genetically distinct from each other. Within the Galapagos Islands, similar sympatric populations may also be isolated from each other, as individuals are not known to switch breeding seasons. The taxonomic relationships among populations of this species that are seasonally and spatially separated are unclear and in need of revision. In this study, playback experiments were used to determine the level of vocal response among prospecting Madeiran Storm‐petrels at colonies in the Azores, Galapagos and Cape Verde islands to recordings from different populations. Vocalizations of all populations studied here differ in their structural characteristics and in all but one case prospecting Storm‐petrels showed far greater response to playback of burrow calls from their own colony type than to calls recorded at other seasonally or geographically distinct colonies. Additionally, the level of response to foreign colony types was no different to playback of vocalizations of an unrelated control species present at the same location. Although not all combinations of geographical and seasonal populations could be examined, the finding that prospecting hot‐season (breeding April–August) Storm‐petrels in the Azores did not differ in their response level to playback from Azores cool‐season (breeding August–March) storm‐petrels and Cory's Shearwaters Calonectris diomedea is of particular significance and suggests the existence of a pre‐mating isolation mechanism that would prevent interbreeding between these two sympatric populations. Furthermore, Azores hot‐season Storm‐petrels showed a similar absence of response to playback from Galapagos dry‐season (May–July) populations, indicating that they are also taxonomically distant from this group. Madeiran Storm‐petrels in the Cape Verde islands showed a low response rate to Azores hot‐season vocalizations, which did not differ from the response to unrelated controls. These data provide further evidence that the hot‐season Azores population represents a distinct taxon that is reproductively isolated from the sympatrically breeding cool‐season population, as well as from more distant populations in the Cape Verde and Galapagos islands.  相似文献   

12.
Abstract The evolution of dioecy was studied in Schiedea (Caryophyllaceae), a genus endemic to the Hawaiian Islands. Eight of the 22 species are diclinous, possessing gynodioecious, subdioecious, or dioecious breeding systems. A biogeographic analysis of the genus indicates that the ancestor of Schiedea colonized early in the history of the Hawaiian Islands. Subsequently, hermaphroditic species appear to have engaged in inter-island colonization more frequently than diclinous species. For this reason, single-island endemism and dicliny are more common on the older Hawaiian Islands. Strong inbreeding depression was detected in three species of Schiedea , indicating that genetic factors have played a role in the evolution of dicliny. Depending on the level of natural selfing, the expression of inbreeding depressioin may have favored the outcrossed progeny of rare females in populations, and eventually the evolution of dioecy. In contrast to evidence for inbreeding depression, there was very little evidence that resource allocation, sex lability, or habitat partitioning have played an important role in the evolution of dioecy. In subdioecious S. globosa hermaphrodites were largely male in function, and in gynodioecious S. salicaria females and hermaphrodites were equivalent in nearly all aspects of female function that could be measured. Variation in breeding systems in Schiedea and the closely related Alsinidendron may result from the past history of population bottlenecks that have resulted in varying levels of inbreeding depression.  相似文献   

13.
The New Zealand Pipit Anthus novaeseelandiae occurs as a single species in Europe (as Richard's Pipit), Asia, Africa, New Guinea, Australia and New Zealand. In the New Zealand region, subspecific status has been accorded to allopatric populations on the mainland (A. n. novaeseelandiae) , on the Auckland and Campbell Islands (A. n. aucklandicus) , on the Antipodes Islands (A. n. steindachneri) and on the Chatham Islands (A. n. chathamensis) . Analyses of 23 allozyme loci and morphometric variation of populations on mainland New Zealand and on the Auckland, Campbell, Antipodes and Chatham Islands showed an appreciable and significant divergence between mainland and island populations. The magnitude of the allozyme difference is sufficient to suggest full species designation for the island birds, a conclusion supported by morphometric analyses and in sharp contrast to current taxonomy. However, formal taxonomic change will not be undertaken until the two New Zealand groups have been compared with more distant populations of this wideranging genus. The cryptic variation found in this species has conservation management implications for the small offshore populations.  相似文献   

14.
Aim The New Zealand avifauna includes lineages that lack close relatives elsewhere and have low diversity, characteristics sometimes ascribed to long geographic isolation. However, extinction at the population and species levels could yield the same pattern. A prominent example is the ecologically important pigeon genus Hemiphaga. In this study, we examined the population structure and phylogeography of Hemiphaga across islands in the region. Location New Zealand, Chatham Islands and Norfolk Island. Methods Mitochondrial DNA was sequenced for all species of the genus Hemiphaga. Sixty‐seven individuals from mainland New Zealand (Hemiphaga novaeseelandiae novaeseelandiae), six of the Chatham Islands sister species (Hemiphaga chathamensis), and three of the extinct Norfolk Island subspecies (Hemiphaga novaeseelandiae spadicea) were included in this study. Novel D‐loop and cytochrome b primers were designed to amplify DNA from museum samples. Additionally, five other mitochondrial genes were used to examine placement of the phylogenetic root. Results Analyses of mitochondrial DNA sequences revealed three Hemiphaga clades, consistent with the allopatric populations of recognized (sub)species on oceanic islands. Of the 23 D‐loop haplotypes among 67 New Zealand pigeons (Hemiphaga n. novaeseelandiae), 19 haplotypes were singletons and one haplotype was common and widespread. Population genetic diversity was shallow within and between New Zealand populations, indicating range expansion with high inter‐population exchange. Tentative rooting of the Hemiphaga clade with cyt b data indicates exchange between mainland New Zealand and the Chatham Islands prior to colonization of Norfolk Island. We found low genetic divergence between populations on New Zealand, the Chatham Islands and Norfolk Island, but deep phylogenetic divergence from the closest living relatives of Hemiphaga. Main conclusions The data are consistent with the hypothesis of population reduction during the Pleistocene and subsequent expansion from forest refugia. Observed mobility of Hemiphaga when feeding helps explain the shallow diversity among populations on islands separated by many hundreds of kilometres of ocean. Together with comparison of distribution patterns observed among birds of the New Zealand region, these data suggest that endemicity might represent not long occupancy of an area, but descent from geologically recent colonizations. We consider the role of lineage pruning in creating the impression of old endemicity.  相似文献   

15.
Aim Determine the phylogeny and dispersal patterns of the cicada genus Kikihia in New Zealand and the origin of the Norfolk, Kermadec, and Chatham Island cicadas. Location New Zealand, Norfolk Island, Kermadec Islands and Chatham Island. Methods DNA sequences from 16 species and four soon to be described species of cicadas from New Zealand and Norfolk Island (Australia) were examined. A total of 1401 base pairs were analysed from whole genome extraction of three mitochondrial genes (cytochrome oxidase subunit II, ATPase6 and ATPase8). These DNA sequences were aligned and analysed using standard likelihood approaches to phylogenetic analysis. Dates of divergences between clades were determined using a molecular clock based on Bayesian statistics. Results Most species in the genus Kikihia diverged between 3 and 5 million years ago (Ma) coincident with a period of rapid mountain building in New Zealand. Cicada species on the Kermadec and Norfolk Islands invaded recently from New Zealand and are closely related to the New Zealand North Island species Kikihia cutora. Main conclusions Speciation in the genus Kikihia was likely due in large part to the appearance of new habitats associated with the rise of the Southern Alps, starting c. 5 Ma. Dispersal of Kikihia species within mainland New Zealand probably occurred gradually rather than through long‐distance jumps. However, invasion of Norfolk, the Kermadecs and Chatham Islands had to have occurred through long‐distance dispersal.  相似文献   

16.
The taxonomic status of petrels from the North East Atlantic has long been a matter of debate. Breeding colonies of petrels occurring on the islands of Madeira, Bugio and Cape Verde were originally thought to be outlying populations of the polytypic species Pterodroma mollis . Subsequent taxonomic treatments have varied considerably in their classification of birds from these islands. The petrel populations on Madeira and Bugio represent some of Europe's rarest breeding birds and their exact species designation, and hence relation to conservation mandates, is a question of considerable importance. In this study we use molecular techniques alongside more traditional taxonomic characters to confirm the existence of two species of the genus Pterodroma in the Archipelago of Madeira. We also discuss identification of these species in the field and the implications for their conservation management.  相似文献   

17.
Aim Pacific biogeographical patterns in the widespread plant genus Melicope J.R. Forst. & G. Forst. (Rutaceae) were examined by generating phylogenetic hypotheses based on chloroplast and nuclear ribosomal sequence data. The aims of the study were to identify the number of colonization events of Melicope to the Hawaiian Islands and to reveal the relationship of Hawaiian Melicope to the Hawaiian endemic genus Platydesma H. Mann. The ultimate goal was to determine if the Hawaiian Islands served as a source area for the colonization of Polynesia. Location Nineteen accessions were sampled in this study, namely eight Melicope species from the Hawaiian Islands, four from the Marquesas Islands, one species each from Tahiti, Australia and Lord Howe Island, two Australian outgroups and two species of the Hawaiian endemic genus Platydesma. To place our results in a broader context, 19 sequences obtained from GenBank were included in an additional analysis, including samples from Australia, Papua New Guinea, New Zealand, Southeast Polynesia and Asia. Methods DNA sequences were generated across 19 accessions for one nuclear ribosomal and three chloroplast gene regions. Maximum parsimony analyses were conducted on separate and combined data sets, and a maximum likelihood analysis was conducted on the combined nuclear ribosomal and chloroplast data set. A broader nuclear ribosomal maximum parsimony analysis using sequences obtained from GenBank was also performed. Geographic areas were mapped onto the combined chloroplast and nuclear ribosomal tree, as well as onto the broader tree, using the parsimony criterion to determine the dispersal patterns. Results Phylogenetic analyses revealed that Platydesma is nested within Melicope and is sister to the Hawaiian members of Melicope. The Hawaiian Melicope + Platydesma lineage was a result of a single colonization event, probably from the Austral region. Finally, Marquesan Melicope descended from at least one, and possibly two, colonization events from the Hawaiian Islands. Main conclusions These data demonstrate a shifting paradigm of Pacific oceanic island biogeography, in which the patterns of long‐distance dispersal and colonization in the Pacific are more dynamic than previously thought, and suggest that the Hawaiian Islands may act as a stepping stone for dispersal throughout the Pacific.  相似文献   

18.
At least four species of New Zealand snipes (Coenocorypha) became extinct following the introduction of predatory mammals, and another two species suffered massive range reductions. To investigate species limits and population differentiation in six of the seven remaining offshore populations, we assayed variation in nine microsatellite loci and 1,980 base pairs of four mitochondrial DNA (mtDNA) genes. Genetic diversity in all populations except the largest one on Adams Island in the Auckland Islands was very low in both genomes. Alleles were fixed at many microsatellite loci and for single mtDNA haplotypes, particularly in the populations in the Chathams, Snares, Antipodes and Campbell Islands. Strong population structure has developed, and Chathams and Snares Islands populations are effectively genetically isolated from one another and from the more southern island populations. Based on reciprocal monophyly of lineages and their morphological distinctiveness we recommend that three phylogenetic species should be recognized, C. pusilla in the Chatham Islands, C. huegeli in the Snares Islands and C. aucklandica in the southern islands. The populations of C. aucklandica in the Auckland Islands, Antipodes Island and Campbell Island may warrant recognition as subspecies, and all should be managed as separate conservation units.  相似文献   

19.
S. Hunter 《Ibis》1984,126(2):119-132
Moult scores were collected from colour-ringed individuals of known reproductive status of the two species of giant petrel, Macronectes halli and M. giganteus , at Bird Island, South Georgia between 1978–81.
Both species showed a substantial overlap between breeding and wing-moult, unlike most other Southern Ocean seabirds. Males started moult before females and both sexes of M. giganteus moulted at an earlier stage of the breeding cycle than M. halli , which breeds six weeks earlier than its congener.
Changes in moult rate during the breeding season are documented for both species, with Id. halli showing a rapid increase as the chick nears fledging. Male M. giganteus show a notably different pattern to the other three species-sex groups, starting moult much earlier (at egg-laying), with greater individual synchrony and usually suspending primary moult throughout the main chick growth period, whereas only two male M. halli and no females of either species suspended moult. Differences in pattern, timing and rate of moult are interpreted in terms of availability of food resources and the competing energy demands of other activities, especially chick-rearing.
Completion of primary moult could not be observed in the field but was estimated using data frcsm non-breeding birds and failed breeders; the latter started a rapid moult almost immediately they failed. In both sexes of both species moult is probably concluded at least by early winter.
The general pattern of moult in giant petrels at Bird Island is contrasted with that of other populations and species of Southern Ocean seabirds. It is suggested that the unusually extensive overlap between breeding and moult in giant petrels is a consequence of the very abundant and easily available summer food supplies (especially carrion) and the much diminished winter resources, favouring a completion of moult by the beginning of the winter.  相似文献   

20.
Tolpis consists of ~13 species native to Africa, Europe, and Macaronesia, with at least one species endemic to each of the four major archipelagos of the Azores, Madeira Islands, Canary Islands, and Cape Verde Islands. All but two of these species develop woody stems by maturity. Chloroplast DNA restriction site variation was analyzed for all species of Tolpis and four outgroups in order to understand the patterns of island colonization and evolution of woodiness in this genus. Parsimony analyses revealed a strongly supported monophyletic Tolpis. Within the genus, the following three well-supported groups were detected: all species from the Canary Islands and Cape Verde Islands, both Azorean species, and both continental species. The Canary Island/Cape Verde clade was sister to the two continental species, and the Azorean clade was sister to this group. The two Madeiran species of Tolpis occupied the basalmost positions within the genus. When biogeography was mapped onto this phylogeny, nine equally parsimonious reconstructions (five steps each) of dispersal history were detected, which fell into two groups: eight reconstructions implied that Tolpis colonized Madeira from the continent, followed by continental extinction and subsequent continental recolonization, while one reconstruction implied that Tolpis colonized Macaronesia four times. Two of the reconstructions involving continental extinction required the least amount of overall dispersal distance. The cpDNA phylogeny also suggests that woodiness arose in the common ancestor of all extant Tolpis, followed by two independent reversals to an herbaceous habit. Assuming that one of the eight reconstructions favoring continental extinction and recolonization is true, our results suggest that Tolpis may represent the first documented example of a woody plant group in Macaronesia that has recolonized the mainland in herbaceous form.  相似文献   

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