scholarly journals Introduced parasite changes host phenotype, mating signal and hybridization risk: Philornis downsi effects on Darwin's finch song

2019 ◽  
Vol 286 (1904) ◽  
pp. 20190461 ◽  
Author(s):  
Sonia Kleindorfer ◽  
Georgina Custance ◽  
Katharina J. Peters ◽  
Frank J. Sulloway
Keyword(s):  
Parental Species ◽  
Maximum Frequency ◽  
Small Tree ◽  
Evolutionary Trajectory ◽  
Philornis Downsi ◽  
Lower Maximum ◽  
Vocal Quality ◽  
Mating Signal ◽  
The 1960S ◽  
Species Specific

Introduced parasites that alter their host's mating signal can change the evolutionary trajectory of a species through sexual selection. Darwin's Camarhynchus finches are threatened by the introduced fly Philornis downsi that is thought to have accidentally arrived on the Galapagos Islands during the 1960s. The P. downsi larvae feed on the blood and tissue of developing finches, causing on average approximately 55% in-nest mortality and enlarged naris size in survivors. Here we test if enlarged naris size is associated with song characteristics and vocal deviation in the small tree finch ( Camarhynchus parvulus ), the critically endangered medium tree finch ( C. pauper ) and the recently observed hybrid tree finch group ( Camarhynchus hybrids). Male C. parvulus and C. pauper with enlarged naris size produced song with lower maximum frequency and greater vocal deviation, but there was no significant association in hybrids. Less vocal deviation predicted faster pairing success in both parental species. Finally, C. pauper males with normal naris size produced species-specific song, but male C. pauper with enlarged naris size had song that was indistinguishable from other tree finches. When parasites disrupt host mating signal, they may also facilitate hybridization. Here we show how parasite-induced naris enlargement affects vocal quality, resulting in blurred species mating signals.

scholarly journals Molecular and morphological approaches for species delimitation and hybridization investigations of two Cichla species

2017 ◽  
Vol 107 (0) ◽  
Author(s):  
Andrea A. F. Mourão ◽  
Diogo Freitas-Souza ◽  
Diogo T. Hashimoto ◽  
Daniela C. Ferreira ◽  
Fernanda D. do Prado ◽  
...  
Keyword(s):  
Species Delimitation ◽  
Parental Species ◽  
Future Research ◽  
Correct Identification ◽  
Pcr Multiplex ◽  
Pcr Rflp ◽  
Genetic Pattern ◽  
Morphometric Methods ◽  
Species Specific ◽  
Specific Nucleotide

ABSTRACT The hybridization is a widely-discussed issue in several studies with fish species. For some authors, hybridization may be related with diversification and speciation of several groups, or also with the extinction of populations or species. Difficulties to differentiate species and hybrids may be a problem to correctly apply a management of wild species, because hybrid lineages, especially the advanced ones, may resemble the parental species. The genus Cichla Bloch & Schneider, 1801 constitutes an interesting experimental model, considering that hybridization and taxonomic uncertainties hinder a correct identification. Considering these problems, in this study, we developed genetic methodologies and applied meristic and morphometric approaches in wild samples in order to identify species and for test a possible hybridization between Cichla kelberi Kullander & Ferreira, 2006 and Cichla piquiti Kullander & Ferreira, 2006. For this, C. kelberi, C. piquiti and potential hybrid ( carijó) individuals were collected in Paraná and Tietê rivers (SP, Brazil). For meristic and morphometric methods, the individuals were analyzed using the statistical software Pcord 5:31, while for molecular methods, primers for PCR-multiplex were designed and enzyme for PCR-RFLP were selected, under the species-specific nucleotide. All results indicated that the carijó is not an interspecific hybrid, because it presented identical genetic pattern and morphology closed to C. piquiti. Thus, we propose that carijó is a C. piquiti morphotype. In addition, this study promotes a new molecular tool that could be used in future research, monitoring and management programs of the genus Cichla.

scholarly journals COMPENSATION EFFECT OF MORTALITY: A CHALLENGE TO LIFE EXTENSION

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S966-S967
Author(s):  
Natalia S Gavrilova ◽  
Leonid Gavrilov
Keyword(s):  
Life Span ◽  
Compensation Effect ◽  
Life Extension ◽  
Slope Parameter ◽  
Aging Rate ◽  
Convergence Point ◽  
Gompertz Law ◽  
The 1960S ◽  
The Stability ◽  
Species Specific

Abstract In order to develop genuine anti-aging interventions it is important to find the best estimate of the aging rate in humans, which is often measured as a slope parameter of the Gompertz law. The compensation effect of mortality (CEM), refers to mortality convergence, when higher values for the slope parameter are compensated by lower values of the intercept parameter (initial mortality) in different populations of a given species. The age of this convergence point is called the "species-specific life span". Due to CEM, factors associated with life span extension are usually accompanied by paradoxical increase in actuarial aging rate. We evaluated the stability of CEM by analyzing the United Nations abridged life tables for 241 countries and regions and estimating parameters of the Gompertz-Makeham model using method of non-linear regression in the age interval 30-80 years. We found that the species-specific lifespan is equal to 94.5 ± 0.5 years, which is the same as reported in the past for years before the 1960s: 95 ± 3 years (Gavrilov, Gavrilova, 1991). Thus, the convergence point of CEM is stable despite significant mortality decline over past 50 years and is not affected by factors decreasing mortality at younger ages. Populations deviating from CEM with apparently slow aging (with both slow actuarial aging rate and low intercept parameter) have been identified. The existence of CEM in mice (ITP data) allowed us to find interventions that are able to both extend lifespan and slow the actuarial aging rate giving promise for radical life extension.

An intergeneric hybrid in the family Phocoenidae

1998 ◽  
Vol 76 (1) ◽  
pp. 198-204 ◽  
Author(s):  
Robin W Baird ◽  
Pamela M Willis ◽  
Tamara J Guenther ◽  
Paul J Wilson ◽  
Bradley N White
Keyword(s):  
Dna Sequences ◽  
Parental Species ◽  
Intergeneric Hybrid ◽  
Harbour Porpoise ◽  
Colour Pattern ◽  
Phocoena Phocoena ◽  
Female Fetus ◽  
The Family ◽  
In The Wild ◽  
Species Specific

A 60-cm female fetus recovered from a Dall's porpoise (Phocoenoides dalli) found dead in southern British Columbia was fathered by a harbour porpoise (Phocoena phocoena). This is the first report of a hybrid within the family Phocoenidae and one of the first well-documented cases of cetacean hybridization in the wild. In several morphological features, the hybrid was either intermediate between the parental species (e.g., vertebral count) or more similar to the harbour porpoise than to the Dall's porpoise (e.g., colour pattern, relative position of the flipper, dorsal fin height). The fetal colour pattern (with a clear mouth-to-flipper stripe, as is found in the harbour porpoise) is similar to that reported for a fetus recovered from a Dall's porpoise to off California. Hybrid status was confirmed through genetic analysis, with species-specific repetitive DNA sequences of both the harbour and Dall's porpoise being found in the fetus. Atypically pigmented porpoises (usually traveling with and behaving like Dall's porpoises) are regularly observed in the area around southern Vancouver Island. We suggest that these abnormally pigmented animals, as well as the previously noted fetus from California, may also represent hybridization events.

scholarly journals Origins and Evolution of Methicillin-Resistant Staphylococcus aureus Clonal Lineages

2006 ◽  
Vol 50 (10) ◽  
pp. 3237-3244 ◽  
Author(s):  
A. R. Gomes ◽  
H. Westh ◽  
H. de Lencastre
Keyword(s):  
Staphylococcus Aureus ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Methicillin Resistance ◽  
Evolutionary Trajectory ◽  
Phage Group ◽  
Genetic Traits ◽  
Methicillin Resistant ◽  
Group Iii ◽  
Resistance To Penicillin ◽  
The 1960S

ABSTRACT Most methicillin-resistant Staphylococcus aureus (MRSA) isolates identified among blood isolates collected in Denmark between 1957 and 1970 belonged to either phage group III or the closely related 83A complex and had a PSTM antibiotype (resistance to penicillin [P], streptomycin [S], tetracycline [T], and methicillin [M]). Recently, some of these isolates were shown to have the same genetic backgrounds as contemporary epidemic MRSA isolates, and Danish methicillin-susceptible S. aureus (MSSA) isolates from the 1960s with a PST antibiotype were proposed to have been the recipients of the mecA gene in those lineages. In this study, we investigated the genetic backgrounds of isolates from the 83A complex that were fully susceptible or resistant to penicillin only in order to try to trace the evolutionary trajectory of contemporary MRSA lineages. We also studied MSSA and MRSA isolates from other phage groups in order to investigate if they had the potential to develop into contemporary MRSA clones. Most susceptible or penicillin-resistant isolates from phage group III or the 83A complex belonged to sequence type 8 (ST8) or ST5, while four isolates were ST254. STs 30, 45 and 25 were represented by MSSA isolates from other phage groups, which also included several singletons. Representatives of most of the current major epidemic MRSA lineages were identified among fully susceptible isolates collected in the 1960s, suggesting that these were MSSA lineages which carried genetic traits important for superior epidemicity before the acquisition of methicillin resistance.

Characterization of Waterhemp (Amaranthus tuberculatus) × Smooth Pigweed (A. hybridus) F1Hybrids

2006 ◽  
Vol 20 (1) ◽  
pp. 14-22 ◽  
Author(s):  
Federico Trucco ◽  
Tatiana Tatum ◽  
Kenneth R. Robertson ◽  
A. Lane Rayburn ◽  
Patrick J. Tranel
Keyword(s):  
Dna Content ◽  
Parental Species ◽  
Hybrid Sterility ◽  
Field Surveys ◽  
Amaranthus Tuberculatus ◽  
Cytogenetic Analyses ◽  
Morphological Differences ◽  
Species Specific ◽  
Natural Settings ◽  
Smooth Pigweed

In the state of Illinois, waterhemp and smooth pigweed are among the worst agricultural weeds. Previous research shows high potential for hybridization between these two species. However, the actual occurrence of hybrids in natural settings is still uncertain. Morphological similarity between hybrids and waterhemp makes field surveys of hybrids difficult to conduct. The main purpose of this study was to characterize the morphology of waterhemp × smooth pigweed F1hybrids, emphasizing evaluation of characters that may allow for hybrid discrimination in fieldAmaranthuscommunities. Concurrently, the study characterized hybrid reproductive fitness, chromosome number, and DNA content. To accomplish this, hybrids were obtained from field crosses. A species-specific polymorphism in theALSgene was used to verify hybrid identity. Significant differences (α = 0.05) between hybrids and individuals of the parental species were observed for five staminate and five carpellate characters. Of these, five characters differentiated hybrids from waterhemp. However, clustering analyses using these characters indicated that morphological differences were not reliable enough, by themselves, for unambiguous hybrid identification. Also, hybrid homoploidy (2n= 32) with respect to parental species excluded chromosome counts in hybridity determinations. However, DNA content analysis may be used for such purpose. Hybrids had an average of 1.21 pg of DNA per 2C nucleus, a value intermediate to that of parental species. Hybrids produced 3.3 or 0.7% the seed output of parental and sibling waterhemp individuals, respectively. Percent micropollen in hybrids was 95-times greater than in parental species. Hybrid sterility appears to be the most reliable feature for hybrid discrimination when conducting field surveys. However, molecular and cytogenetic analyses as employed in this study may be desired for ultimate identity corroboration.

scholarly journals Hybrid speciation leads to novel male secondary sexual ornamentation of an Amazonian bird

2017 ◽  
Vol 115 (2) ◽  
pp. E218-E225 ◽  
Author(s):  
Alfredo O. Barrera-Guzmán ◽  
Alexandre Aleixo ◽  
Matthew D. Shawkey ◽  
Jason T. Weir
Keyword(s):  
Amazon Basin ◽  
Parental Species ◽  
Genetic Admixture ◽  
Hybrid Speciation ◽  
Premating Isolation ◽  
Hybrid Species ◽  
Speciation Event ◽  
A Genome ◽  
Admixture Population ◽  
Species Specific

Hybrid speciation is rare in vertebrates, and reproductive isolation arising from hybridization is infrequently demonstrated. Here, we present evidence supporting a hybrid-speciation event involving the genetic admixture of the snow-capped (Lepidothrix nattereri) and opal-crowned (Lepidothrix iris) manakins of the Amazon basin, leading to the formation of the hybrid species, the golden-crowned manakin (Lepidothrix vilasboasi). We used a genome-wide SNP dataset together with analysis of admixture, population structure, and coalescent modeling to demonstrate that the golden-crowned manakin is genetically an admixture of these species and does not represent a hybrid zone but instead formed through ancient genetic admixture. We used spectrophotometry to quantify the coloration of the species-specific male crown patches. Crown patches are highly reflective white (snow-capped manakin) or iridescent whitish-blue to pink (opal-crowned manakin) in parental species but are a much less reflective yellow in the hybrid species. The brilliant coloration of the parental species results from nanostructural organization of the keratin matrix feather barbs of the crown. However, using electron microscopy, we demonstrate that the structural organization of this matrix is different in the two parental species and that the hybrid species is intermediate. The intermediate nature of the crown barbs, resulting from past admixture appears to have rendered a duller structural coloration. To compensate for reduced brightness, selection apparently resulted in extensive thickening of the carotenoid-laden barb cortex, producing the yellow crown coloration. The evolution of this unique crown-color signal likely culminated in premating isolation of the hybrid species from both parental species.

Characterization of MboI satellites in Cirrhina mrigala and Clarias batrachus (Pisces)

Genome ◽  
1998 ◽  
Vol 41 (1) ◽  
pp. 34-39 ◽  
Author(s):  
Bhaja K Padhi ◽  
Sudip K Ghosh ◽  
Radha K Mandal
Keyword(s):  
Parental Species ◽  
Labeo Rohita ◽  
Clarias Gariepinus ◽  
Clarias Batrachus ◽  
Catla Catla ◽  
Genetic Introgression ◽  
Heteropneustes Fossilis ◽  
Reciprocal Hybrids ◽  
Species Specific

We have cloned and characterized two highly reiterated, tandemly repeated, and A + T rich MboI DNA fragments, one in Cirrhina mrigala (Cyprinidae), with a monomer size of 266 bp, and one in Clarias batrachus (Clariidae), with a monomer size of 227 bp. The MboI fragment in C. mrigala is species-specific and absent in other carps, such as Catla catla and Labeo rohita. The MboI fragment in C. batrachus was also present in two other catfishes tested, namely Clarias gariepinus and Heteropneustes fossilis. In C. mrigala xC. catla and C. mrigala x L. rohita hybrids, the C. mrigala specific MboI fragment is inherited uniparentally. In the reciprocal hybrids of C. batrachus xH. fossilis, the satellite ladder contains the bands of both parental species. The MboI satellite of carp may be useful in genetic introgression analysis and that of catfish in distinguishing between gynogenetic progeny and true hybrids.

scholarly journals Extraordinary centromeres: differences in the meiotic chromosomes of two rock lizards species Darevskia portschinskii and Darevskia raddei

2018 ◽  
Author(s):  
Victor Spangenberg ◽  
Marine Arakelyan ◽  
Eduard Galoyan ◽  
Mark Pankin ◽  
Ruzanna Petrosyan ◽  
...  
Keyword(s):  
Mitotic Chromosome ◽  
Parental Species ◽  
Primary Spermatocyte ◽  
Chromosome Analysis ◽  
Chromatin Modifications ◽  
Future Studies ◽  
Parthenogenetic Species ◽  
Meiotic Chromosomes ◽  
Species Specific ◽  
First Time

According to the synthesis of 30 years of multidisciplinary studies parthenogenetic species of rock lizards of genus Darevskia were formed as a result of different combination patterns of interspecific hybridization of the four bisexual parental species: D. raddei, D. mixta, D. valentini, and D. portschinskii. In particular D. portschinskii and D. raddei are considered as the parental species for the parthenogenetic species D. rostombekowi. Here for the first time we present the result of comparative immunocytochemical study of primary spermatocyte nuclei spreads from the leptotene to diplotene stages of meiotic prophase I in two species: D. portschinskii and D. raddei. We observed similar chromosome lengths for both synaptonemal complex (SC) karyotypes as well as similar number of crossing over sites. However, unexpected differences in the number and distribution of anti-centromere antibody (ACA) foci were detected in the SC structure of bivalents of the two species. In all examined D. portschinskii spermatocyte nuclei, one immunostained centromere focus was detected per SC bivalent. In contrast, in almost every studied D. raddei nuclei we identified three – nine SCs with additional immunostained ACA foci per SC bivalent. Thus, the obtained results allow us to identify species-specific karyotype features, previously not been detected using conventional mitotic chromosome analysis. Presumably the additional centromere foci are result of epigenetic chromatin modifications. We assume that this characteristic of the D. raddei karyotype could represent useful marker for the future studies of parthenogenetic species hybrid karyotypes related to D. raddei.

Species-Specific Auditory Forebrain Responses to Non-Learned Vocalizations in Juvenile Blackbirds

2018 ◽  
Vol 91 (4) ◽  
pp. 193-200 ◽  
Author(s):  
Kathleen S. Lynch ◽  
Matthew I.M. Louder ◽  
Mark E. Hauber
Keyword(s):  
Parental Species ◽  
Species Recognition ◽  
Molothrus Ater ◽  
Early Gene ◽  
Acoustic Similarity ◽  
Neural Responses ◽  
Closely Related Species ◽  
Auditory Forebrain ◽  
Caudomedial Nidopallium ◽  
Species Specific

Species recognition mediates the association of individuals with conspecifics. Learned cues often facilitate species recognition via early social experience with parents and siblings. Yet, in some songbirds, the production of species-typical vocalizations develops in the absence of early social experiences. Here, we investigate the auditory-evoked neural responses of juvenile red-winged blackbirds (Agelaius phoeniceus), a nonparasitic (parental) species within the Icterid family and contrast these results with a closely related Icterid parasitic species that lacks parental care, the brown-headed cowbird (Molothrus ater). We demonstrate that immediate early gene (IEG) activity in the caudomedial mesopallium (CMM) is selectively evoked in response to conspecific non-learned vocalizations in comparison to 2 types of heterospecific non-learned vocalizations, independent of the acoustic similarity patterns between the playback stimuli. This pattern, however, was not detected in the caudomedial nidopallium (NCM). Because the red-winged blackbird is a parental species, the conspecific non-learned vocalization is presumably a familiar sound to the juvenile red-winged blackbird, whereas the heterospecific non-learned vocalizations are novel. We contrast results reported here with our recent demonstration of selective IEG induction in response to non-learned conspecific vocalizations in juvenile parasitic brown-headed cowbirds, in which conspecific non-learned vocalizations are presumably novel. In this case, selective IEG induction from conspecific non-learned vocalization occurred within NCM but not within CMM. By comparing closely related species with stark differences in the early exposure to conspecifics, we demonstrate that CMM and NCM respond to familiar vs. novel non-learned vocalizations in a manner that parallel previously reported regional responses to learned vocalizations such as conspecific songs.

scholarly journals Host gene evolution traces the evolutionary history of ancient primate lentiviruses

2013 ◽  
Vol 368 (1626) ◽  
pp. 20120496 ◽  
Author(s):  
Alex A. Compton ◽  
Harmit S. Malik ◽  
Michael Emerman
Keyword(s):  
Gene Evolution ◽  
Primate Species ◽  
Past Century ◽  
Human Populations ◽  
Pathogenic Potential ◽  
Evolutionary Trajectory ◽  
Viral Adaptation ◽  
Minimum Age ◽  
Primate Lentiviruses ◽  
Species Specific

Simian immunodeficiency viruses (SIVs) have infected primate species long before  human immunodeficiency virus has infected humans. Dozens of species-specific lentiviruses are found in African primate species, including two strains that have repeatedly jumped into human populations within the past century. Traditional phylogenetic approaches have grossly underestimated the age of these primate lentiviruses. Instead, here we review how selective pressures imposed by these viruses have fundamentally altered the evolutionary trajectory of hosts genes and, even in cases where there now remains no trace of the viruses themselves, these evolutionary signatures can reveal the types of viruses that were once present. Examination of selection by ancient viruses on the adaptive evolution of host genes has been used to derive minimum age estimates for modern primate lentiviruses. This type of data suggests that ancestors of modern SIV existed in simian primates more than 10 Ma. Moreover, examples of host resistance and viral adaptation have implications not only for estimating the age and host range of ancient primate lentiviruses, but also the pathogenic potential of their modern counterparts.

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