Tag: Evolution

Salojärvi et al. have assembled the genome of silver birch (Betula pendula) and examined genomic diversity across 150 individuals collected from across Northern Europe and Asia. Their study shows that there have been several genetic bottlenecks associated with climate upheaval (e.g., at the K-Pg boundary…

Chromosomal inversions are chromosomal rearrangements that can span several Mb and have been described in several organisms from Drosophila to maize. Inversions suppress recombination and can favor local adaptation and speciation if they capture favorable alleles. It’s not clear though if favorable…

Phytochromes were first characterized in classic studies of plants, in which their contributions to seed germination and initiation of flowering were described. Subsequently, phytochromes were identified in cyanobacteria and in non-photosynthetic organisms including fungi. Rockwell and Lagarias review…

The ancestors of land plants were aquatic. Myriad changes accompanied the transition from aquatic to terrestrial life, including changes necessitated by the difference in light intensity and quality. Bryophytes, the earliest diverging land plants, have some characteristics that reveal how plants transitioned…

Trans-acting small interfering RNAs (tasiRNAs) are unique to plants. They are the products of TAS genes, but they function to regulate other genes (thus the name “trans-acting”). The production of tasiRNAs requires miRNAs, which bind to and ultimately lead to cleavage of the primary TAS transcript.…

It is well established that plastids are derived from the primary endosymbiosis of an ancient cyanobacterium into a eukaryotic host cell, but this understanding does not explain all of the evidence, nor does it explain how the nascent endosymbiont evaded the host cell's defense mechanisms. Recently,…

There are many subspecies of Brassica rapa [including turnip (subsp. rapa) pak choi (subsp. chinensis) and Chinese cabbage (subsp. pekinensis)] but the relationships between the subspecies has remained uncertain. Qi et al. sequenced 143 accessions, including some subspecies for the first time. They then…

Crop domestication has been accompanied by the evolution of aggressive weedy crop relatives that compete for resources and make weed management a challenge. By using whole-genome sequencing of the two most commonly found weedy rice strains in the US (SH and BHA), and comparing them with the genomes of…