Plasticity versus Evolutionary Divergence: What Causes Habitat Partitioning in Urban-Adapted Birds?

The origin of the Neogene planktonic foraminifer Globorotalia (Globoconella) pliozea in the subtropical southwest Pacific has been attributed to its isolation resulting from intensification of the Subtropical Divergence (Tasman Front). Oxygen isotopic analyses suggest that, although the Subtropical Divergence may have played a role, the evolution of Gr. (G.) pliozea was facilitated by depth segregation of Gr. (G.) conomiozea morphotypes (low and high conical) during an interval of near-surface warming and increasing thermal gradient. Oxygen isotopic analyses suggest that low conical morphotypes of Gr. (G.) conomiozea inhabited greater depths than high conical morphotypes. Low conical forms of Gr. (G.) conomiozea are considered ancestral to the low conical species, Gr. (G.) pliozea. Oxygen isotopes indicate that Gr. (G.) pliozea inhabited greater depths than its ancestor, Gr. (G.) conomiozea.These data are consistent with depth-parapatric and depth-allopatric models, but not with a sympatric model of speciation. In the allopatric model, reproduction at different water depths acts as a barrier between morphotypes. In the parapatric model, clinal variation along a depth gradient acts as a barrier between morphotypes living at the limits of the gradient. Depth segregation in both models results in genetic isolation and evolutionary divergence. Our data support a correlation between morphological evolution and habitat changes in the Globoconella clade, implying separation of populations as a driving force for morphological evolution.Ecological segregation of morphotypes and species may be related to morphology (height of the conical angle), based on the data from Gr. (G.) conomiozea and Gr. (G.) pliozea. However, morphological differences alone do not necessarily produce depth differences. Large morphological differences between Gr. (G.) pliozea and closely related Gr. (G.) puncticulata did not result in isotopic and therefore depth differences between these species. These species coexisted at the same water depths for nearly 1 m.y. Thus, it is unlikely that the extinction of Gr. (G.) pliozea in the middle Pliocene resulted from competition with Gr. (G.) puncticulata, as previously suggested.

Download Full-text

Expansion and accelerated evolution of 9-exon odorant receptors in Polistes paper wasps

Molecular Biology and Evolution ◽

10.1093/molbev/msab023 ◽

2021 ◽

Author(s):

Andrew W Legan ◽

Christopher M Jernigan ◽

Sara E Miller ◽

Matthieu F Fuchs ◽

Michael J Sheehan

Keyword(s):

Gene Family ◽

Odorant Receptor ◽

Receptor Gene ◽

Gene Tree ◽

Gene Family Evolution ◽

Paper Wasp ◽

Gene Copy ◽

Evolutionary Divergence ◽

Wasp Species ◽

Or Gene

Abstract Independent origins of sociality in bees and ants are associated with independent expansions of particular odorant receptor (OR) gene subfamilies. In ants, one clade within the OR gene family, the 9-exon subfamily, has dramatically expanded. These receptors detect cuticular hydrocarbons (CHCs), key social signaling molecules in insects. It is unclear to what extent 9-exon OR subfamily expansion is associated with the independent evolution of sociality across Hymenoptera, warranting studies of taxa with independently derived social behavior. Here we describe odorant receptor gene family evolution in the northern paper wasp, Polistes fuscatus, and compare it to four additional paper wasp species spanning ∼40 million years of evolutionary divergence. We find 200 putatively functional OR genes in P. fuscatus, matching predictions from neuroanatomy, and more than half of these are in the 9-exon subfamily. Most OR gene expansions are tandemly arrayed at orthologous loci in Polistes genomes, and microsynteny analysis shows species-specific gain and loss of 9-exon ORs within tandem arrays. There is evidence of episodic positive diversifying selection shaping ORs in expanded subfamilies. Values of omega (d N/dS) are higher among 9-exon ORs compared to other OR subfamilies. Within the Polistes OR gene tree, branches in the 9-exon OR clade experience relaxed negative (purifying) selection relative to other branches in the tree. Patterns of OR evolution within Polistes are consistent with 9-exon OR function in CHC perception by combinatorial coding, with both natural selection and neutral drift contributing to interspecies differences in gene copy number and sequence.

Download Full-text

Xenopus laevis integrins. Structural conservation and evolutionary divergence of integrin beta subunits.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)60720-3 ◽

1988 ◽

Vol 263 (11) ◽

pp. 5333-5340

Author(s):

D W DeSimone ◽

R O Hynes

Keyword(s):

Xenopus Laevis ◽

Beta Subunits ◽

Evolutionary Divergence ◽

Structural Conservation

Download Full-text

Discovery of Evolutionary Divergence of Biological Nitrogen Fixation and Photosynthesis: Fine Tuning of Biogenesis of the NifH and the ChlL by a Peptidyl-Prolyl Cis/Trans Isomerase

American Journal of Biochemistry and Biotechnology ◽

10.3844/ajbbsp.2011.196.203 ◽

2011 ◽

Vol 7 (4) ◽

pp. 196-203

Author(s):

Rachid

Keyword(s):

Nitrogen Fixation ◽

Biological Nitrogen Fixation ◽

Fine Tuning ◽

Evolutionary Divergence ◽

Biological Nitrogen

Download Full-text

Mangrove tree (Avicennia marina): insight into chloroplast genome evolutionary divergence and its comparison with related species from family Acanthaceae

Scientific Reports ◽

10.1038/s41598-021-83060-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sajjad Asaf ◽

Abdul Latif Khan ◽

Muhammad Numan ◽

Ahmed Al-Harrasi

Keyword(s):

Chloroplast Genome ◽

Related Species ◽

Evolutionary Genetics ◽

Single Copy ◽

Avicennia Marina ◽

Pairwise Distance ◽

Trna Genes ◽

Evolutionary Divergence ◽

Mangrove Tree ◽

High Degree

AbstractAvicennia marina (family Acanthaceae) is a halotolerant woody shrub that grows wildly and cultivated in the coastal regions. Despite its importance, the species suffers from lack of genomic datasets to improve its taxonomy and phylogenetic placement across the related species. Here, we have aimed to sequence the plastid genome of A. marina and its comparison with related species in family Acanthaceae. Detailed next-generation sequencing and analysis showed a complete chloroplast genome of 150,279 bp, comprising 38.6% GC. Genome architecture is quadripartite revealing large single copy (82,522 bp), small single copy (17,523 bp), and pair of inverted repeats (25,117 bp). Furthermore, the genome contains 132 different genes, including 87 protein-coding genes, 8 rRNA, 37 tRNA genes, and 126 simple sequence repeats (122 mononucleotide, 2 dinucleotides, and 2 trinucleotides). Interestingly, about 25 forward, 15 reversed and 14 palindromic repeats were also found in the A. marina. High degree synteny was observed in the pairwise alignment with related genomes. The chloroplast genome comparative assessment showed a high degree of sequence similarity in coding regions and varying divergence in the intergenic spacers among ten Acanthaceae species. The pairwise distance showed that A. marina exhibited the highest divergence (0.084) with Justicia flava and showed lowest divergence with Aphelandra knappiae (0.059). Current genomic datasets are a valuable resource for investigating the population and evolutionary genetics of family Acanthaceae members’ specifically A. marina and related species.

Download Full-text