What's the difference between homoplasmy and homoplasy?
Homoplasmy
Definition:
(n.) Resemblance between different plants or animals, in external shape, in general habit, or in organs, which is not due to descent from a common ancestor, but to similar surrounding circumstances.
Example Sentences:
(1) There is usually only one mitochondrial DNA population (homoplasmy) within an individual.
(2) Transmission of mutant mtDNA through these three generations did not show any tendency toward homoplasmy.
(3) By following the transmission of a heteroplasmic mitochondrial DNA mutation through four generations of Holstein cows, we have documented that substantial shifts in the levels of heteroplasmy can occur between single mammalian generations, that neutral mitochondrial genotypes can segregate in different directions in offspring of the same female, and that a return to homoplasmy may occur in only two or three generations.
(4) This observation suggests that the nt 11778 mutation observed in this LHON family is relatively new; the observation of both heteroplasmy and apparent homoplasmy of the mtDNA in different family members might reflect the normal progression in the establishment of a mitochondrially inherited mutation.
Homoplasy
Definition:
(n.) See Homogeny.
Example Sentences:
(1) Although the distribution of enamel prism packing patterns among primates suggests considerable homoplasy of this character, this feature does have considerable taxonomic interest at certain hierarchical levels in Primates.
(2) Homoplasy is as prevalent at the few variable sites of conserved regions (18E, 18J, 28F) as at the many variable sites of a more rapidly evolving region (28B).
(3) The pattern with considerable overlap, found in the three classes of amniotes, should be considered an independent development from the same primitive character and should, therefore, be defined as an example of parallel homoplasy.
(4) Further data are needed to decide whether the cell groups in Platyrhinoidis are homologous or homoplasious to their counterparts in land vertebrates.
(5) Cladograms consistently recovered accepted higher level relationships (monophyly of Lepidoptera), despite high homoplasy, but were unable to resolve superfamily and family relationships within Lepidoptera, regardless of the outgroup or character subset analyzed.
(6) Cladistic analyses indicate that the variation in presence of anterior ventral glands is due to homoplasy.
(7) Assignment of observed base substitutions occurring in various branches of the tree reveals an excess of would-be homoplasies in a centrally localized 1.8-kb segment containing the s15 gene.
(8) Matrices of delta Tm's, delta modes, and delta T50Hs were generated and corrected for nonreciprocity, homoplasy, and, in the case of delta Tm's, normalized percent hybridization; these matrices were analyzed using the FITCH algorithm in Felsenstein's PHYLIP (version 3.1).
(9) LeQuesne testing can give information about niche homoplasy, and it may also be possible to see if morphological features are functionally associated with ecological parameters, even if the direction of change is unknown.
(10) Further we offer an approach to structural analysis that demonstrates and quantitates the degree of homoplasy in particular positions of a protein.
(11) Of the many possible hypothetical relationships, the most parsimonious tree showed three homoplasies and allowed the genus Gerbillurus to be paraphyletic.
(12) The alternative trees, depicting larger number of homoplasies but with homoplasies restricted to fusion or fission events, were compatible with the morphological data in supporting the monophyly of Gerbillurus.
(13) Homoplasy, in particular, is a difficulty faced by all methods of phylogenetic inference.
(14) The main primary reasons for untrue or inexplicit morphological phylogenies are: not enough characters developed between branching points, uncertain character polarity, poorly differentiated character states, homoplasy caused by parallelism or reversal, and extinction, which may remove species entirely from consideration and can make originally conflicting data sets misleadingly compatible, increasing congruence at the expense of truth.
(15) The demonstration of extensive homoplasy in a malaria gene raises questions about the validity of familial relationships established among parasites with polymorphic markers.
(16) These include 1) the uncritical assumption of parsimony, 2) uncertainties in the identification of homoplasies, 3) difficulties in the appropriate delimitation of samples for analysis, 4) failure to account for normal patterns of variation, 5) methodological problems with the appropriate identification of morphological traits involving issues of biological relevance, intercorrelation, primary versus secondary characters, and the use of continuous variables, 6) issues of polarity identification, and 7) problems in hypothesis testing.
(17) Further, paleobiogeographic data support the DNA tree rather than the morphological tree, and a plausible heterochronic mechanism has been proposed that may account for the homoplasious morphological evolution that must have occurred if the DNA tree is correct.
(18) An analysis of expected and observed homoplasy revealed that the number of sequence changes uniquely shared by human and chimpanzee lineages is too large to be attributed to homoplasy.
(19) Furthermore, a critical analysis of potential sources of homoplasy (i.e., parallel evolution) reaffirms a Homo-Pan monophyletic clade (Miyamoto et al., 1987).
(20) We suggest that homoplasy at particular positions could mark a site of biological pressure on the parasite where interaction of the site with factors in the environment affects the success of the parasite population.