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Novelties of the flowering plant pollen tube underlie diversification of a key life history stage
  • J. Williams
  • Environmental Science
    Proceedings of the National Academy of Sciences
  • 12 August 2008
TLDR
Comparative analyses point to accelerated pollen tube growth rate as a critical innovation that preceded the origin of the true closed carpel, long styles, multiseeded ovaries, and, in monocots and eudicots, much faster pollen tubes growth rates.
NATURAL HYBRIDIZATION: HOW LOW CAN YOU GO AND STILL BE IMPORTANT?
TLDR
This paper examines two assumptions that have formed the basis for much of the past and present work on hybrid zones and demonstrates that various hybrid genotypes have equivalent or higher fitness than their parents in certain habitats.
HOW DISCRETE ARE OAK SPECIES? INSIGHTS FROM A HYBRID ZONE BETWEEN QUERCUS GRISEA AND QUERCUS GAMBELII
TLDR
A set of RAPD markers that distinguish between the white oaks Quercus gambelii and Q. grisea are described and used to examine patterns of gene exchange in an area of contact in the San Mateo Mountains of New Mexico, confirming that hybridization between the two species takes place.
Pollination biology of basal angiosperms (ANITA grade).
TLDR
It is hypothesized that large flowers in Nymphaeaceae are the result of the interaction of heat, floral odors, and colored tepals to trap insects to increase fitness.
The four-celled female gametophyte of Illicium (Illiciaceae; Austrobaileyales): implications for understanding the origin and early evolution of monocots, eumagnoliids,and eudicots.
TLDR
A character analysis based on more than 250 embryological studies indicates that a transition from an ancestrally four-celled/four-nucleate Illicium-like female gametophyte to a seven-CElled/eight-n nucleate female gamETophyte occurred in the common ancestor of the sister group to Austrobaileyales.
Amborella trichopoda (Amborellaceae) and the evolutionary developmental origins of the angiosperm progamic phase.
TLDR
New data from Amborella and a review of fertilization biology of other early-divergent angiosperms show that an evolutionary transition from slow reproduction to rapid reproduction occurred early in angiosperm history.
Reproductive processes in two oak (Quercus) contact zones with different levels of hybridization
TLDR
Early postfertilization processes play a strong role in species fidelity in these oaks, and the Environmental Emasculation Hypothesis that posits that environmental stress can increase the probability of hybrid formation by reducing the competitive ability of male gametes of one species is proposed is proposed.
POLLEN TUBE GROWTH RATES AND THE DIVERSIFICATION OF FLOWERING PLANT REPRODUCTIVE CYCLES
TLDR
Angiosperm pollen tube walls consist largely of callose and contain far less material than do tube walls of other seed plants, which have little or no callose but high cellulose and pectin content.
MODULARITY OF THE ANGIOSPERM FEMALE GAMETOPHYTE AND ITS BEARING ON THE EARLY EVOLUTION OF ENDOSPERM IN FLOWERING PLANTS
TLDR
Comparative analysis of onto‐genetic sequences suggests that the seven‐celled female gametophyte (two modules) evolved by duplication and ectopic expression of an ancestral Nuphar‐ like developmental module within the chalazal domain of the female gamETophyte.
Origin of the Fittest and Survival of the Fittest: Relating Female Gametophyte Development to Endosperm Genetics
TLDR
It is demonstrated that variation in female gametophyte developmental patterns represents the source material that ultimately creates variation in endosperm genetics and is seen as one between the origin of structural novelties and its downstream consequences on the relative fitness of these novelties, as expressed in the biology of endosperms.
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