scholarly journals Fin whale (Balaenoptera physalus) mitogenomics: A cautionary tale of defining sub-species from mitochondrial sequence monophyly

2018 ◽  
Author(s):  
Andrea A. Cabrera ◽  
Jeroen P. A. Hoekendijk ◽  
Alex Aguilar ◽  
Susan G. Barco ◽  
Simon Berrow ◽  
...  
Keyword(s):  
Mitochondrial Genome ◽  
Genetic Drift ◽  
North Atlantic ◽  
Dna Sequences ◽  
Common Ancestor ◽  
Complete Mitochondrial Genome ◽  
Recent Common Ancestor ◽  
Balaenoptera Physalus ◽  
Fin Whale ◽  
Fin Whales

HighlightsMitochondrial monophyly is commonly employed to define evolutionary significant units.Monophyly may be caused by insufficient sampling or a recent common ancestor.Mitogenomic studies are generally based on few samples and prone to sampling issues.Expanded mitogenome sampling negates previous monophyly in fin whales.AbstractThe advent of massive parallel sequencing technologies has resulted in an increase of studies based upon complete mitochondrial genome DNA sequences that revisit the taxonomic status within and among species. Spatially distinct monophyly in mitogenomic genealogies, i.e., the sharing of a recent common ancestor among con-specific samples collected in the same region has been viewed as evidence for subspecies. Several recent studies in cetaceans have employed this criterion to suggest subsequent intraspecific taxonomic revisions. We reason that employing intra-specific, spatially distinct monophyly at non-recombining, clonally inherited genomes is an unsatisfactory criterion for defining subspecies based upon theoretical (genetic drift) and practical (sampling effort) arguments. This point is illustrated by a re-analysis of a global mitogenomic assessment of fin whales, Balaenoptera physalus spp., published by Archer et al. (2013) which proposed to further subdivide the Northern Hemisphere fin whale subspecies, B. p. physalus. The proposed revision was based upon the detection of spatially distinct monophyly among North Atlantic and North Pacific fin whales in a genealogy based upon complete mitochondrial genome DNA sequences. The extended analysis conducted in this study (1,676 mitochondrial control region, 162 complete mitochondrial genome DNA sequences and 20 microsatellite loci genotyped in 358 samples) revealed that the apparent monophyly among North Atlantic fin whales reported by Archer et al. (2013) to be due to low sample sizes. In conclusion, defining sub-species from monophyly (i.e., the absence of para-or polyphyly) can lead to erroneous conclusions due to relatively “trivial” aspects, such as sampling. Basic population genetic processes (i.e., genetic drift and migration) also affect the time to most recent common ancestor and hence the probability that individuals in a sample are monophyletic.

Revision of fin whale Balaenoptera physalus (Linnaeus, 1758) subspecies using genetics

2019 ◽  
Vol 100 (5) ◽  
pp. 1653-1670 ◽  
Author(s):  
Frederick I Archer ◽  
Robert L Brownell ◽  
Brittany L Hancock-Hanser ◽  
Phillip A Morin ◽  
Kelly M Robertson ◽  
...  
Keyword(s):  
North Atlantic ◽  
North Pacific ◽  
Recent Analysis ◽  
Snp Analysis ◽  
Balaenoptera Physalus ◽  
Data Set ◽  
Fin Whale ◽  
The North ◽  
Fin Whales ◽  
The North Pacific

Abstract Three subspecies of fin whales (Balaenoptera physalus) are currently recognized, including the northern fin whale (B. p. physalus), the southern fin whale (B. p. quoyi), and the pygmy fin whale (B. p. patachonica). The Northern Hemisphere subspecies encompasses fin whales in both the North Atlantic and North Pacific oceans. A recent analysis of 154 mitogenome sequences of fin whales from these two ocean basins and the Southern Hemisphere suggested that the North Pacific and North Atlantic populations should be treated as different subspecies. Using these mitogenome sequences, in this study, we conduct analyses on a larger mtDNA control region data set, and on 23 single-nucleotide polymorphisms (SNPs) from 144 of the 154 samples in the mitogenome data set. Our results reveal that North Pacific and North Atlantic fin whales can be correctly assigned to their ocean basin with 99% accuracy. Results of the SNP analysis indicate a correct classification rate of 95%, very low rates of gene flow among ocean basins, and that distinct mitogenome matrilines in the North Pacific are interbreeding. These results indicate that North Pacific fin whales should be recognized as a separate subspecies, with the name B. p. velifera Cope in Scammon 1869 as the oldest available name.

scholarly journals Crassicauda boopis in a fin whale (Balaenoptera physalus) ship-struck in the eastern North Atlantic Ocean

2017 ◽  
Vol 3 ◽  
Author(s):  
LAETITIA LEMPEREUR ◽  
MORGAN DELOBELLE ◽  
MARJAN DOOM ◽  
JAN HAELTERS ◽  
ETIENNE LEVY ◽  
...  
Keyword(s):  
North Atlantic ◽  
18S Rrna ◽  
North Atlantic Ocean ◽  
18S Rrna Gene ◽  
The Body ◽  
Rrna Gene ◽  
Balaenoptera Physalus ◽  
Fin Whale ◽  
Eastern North Atlantic ◽  
The Right

SUMMARY On 9 November 2015, a juvenile male fin whale of 11·60 m length was observed on the bulb of a merchant vessel in the Channel Terneuzen – Ghent (The Netherlands – Belgium). A severe parasitosis was present in the right heart ventricle and caudal caval vein. Parasites were identified as Crassicauda boopis based on macroscopic and microscopic observations. The sequence of the 18S rRNA gene obtained from the parasite samples was 100% similar to the sequence of the 18S rRNA gene from Crassicauda magna available on GenBank. While adults of C. boopis and C. magna are morphologically distinct and found at different locations in the body, the molecular analysis of the 18S rRNA gene seems insufficient for reliable species identification. Although numerous C. boopis were found, the cause of death was identified as due to the collision with the ship, as suggested by the presence of a large haematoma, and the absence of evidence of renal failure. The young age of this whale and the absence of severe chronic reaction may suggest that the infestation was not yet at an advanced chronic stage.

The distribution, cellular structure, and metabolism of adipose tissue in the fin whale, Balaenoptera physalus

1988 ◽  
Vol 66 (2) ◽  
pp. 534-537 ◽  
Author(s):  
Caroline M. Pond ◽  
Christine A. Mattacks
Keyword(s):  
Adipose Tissue ◽  
North Atlantic ◽  
Glucose Utilization ◽  
Significant Activity ◽  
Balaenoptera Physalus ◽  
Tissue Samples ◽  
Fin Whale ◽  
Terrestrial Mammals ◽  
The North ◽  
Adipocyte Volume

The gross mass, mean adipocyte volume, and hexokinase and phosphofructokinase activities of blubber and internal adipose tissue were measured from fin whales (Balaenoptera physalus) caught in the North Atlantic west of Iceland. Fin whale adipocytes are smaller but more numerous than predictions from allometric equations relating adipose tissue structure to body mass, but the deviations are no greater than those of some terrestrial mammals, including humans. Significant activity of the glycolytic enzymes was measured from all adipose tissue samples except those around the eyeball; the activities of hexokinase and phosphofructokinase measured at room temperature are only slightly lower in the blubber than in the internal adipose depots. There was little evidence for metabolic correlates of the site-specific differences in the structure and chemistry of blubber. The highest capacity for glucose utilization was measured in adipose tissue from depots in the neck and the thorax, both of which may contain thermogenic tissue in neonates.

scholarly journals A new time tree reveals Earth history’s imprint on the evolution of modern birds

2015 ◽  
Vol 1 (11) ◽  
pp. e1501005 ◽  
Author(s):  
Santiago Claramunt ◽  
Joel Cracraft
Keyword(s):  
Dna Sequences ◽  
Plate Tectonics ◽  
Common Ancestor ◽  
Fossil Birds ◽  
Recent Common Ancestor ◽  
Avian Evolution ◽  
Most Recent Common Ancestor ◽  
Global Cooling ◽  
Basic Features ◽  
New Time

Determining the timing of diversification of modern birds has been difficult. We combined DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate a new time tree for Neornithes and investigated their biogeographic and diversification dynamics. We found that the most recent common ancestor of modern birds inhabited South America around 95 million years ago, but it was not until the Cretaceous-Paleogene transition (66 million years ago) that Neornithes began to diversify rapidly around the world. Birds used two main dispersion routes: reaching the Old World through North America, and reaching Australia and Zealandia through Antarctica. Net diversification rates increased during periods of global cooling, suggesting that fragmentation of tropical biomes stimulated speciation. Thus, we found pervasive evidence that avian evolution has been influenced by plate tectonics and environmental change, two basic features of Earth’s dynamics.

A comparison of pigmentation features among North Atlantic killer whale (Orcinus orca) populations

2014 ◽  
Vol 94 (6) ◽  
pp. 1335-1341 ◽  
Author(s):  
Pirjo Mäkeläinen ◽  
Ruth Esteban ◽  
Andrew D. Foote ◽  
Sanna Kuningas ◽  
Julius Nielsen ◽  
...  
Keyword(s):  
North Atlantic ◽  
Common Ancestor ◽  
Killer Whale ◽  
Orcinus Orca ◽  
Recent Common Ancestor ◽  
Killer Whales ◽  
Parallel Orientation ◽  
Local Populations ◽  
Most Recent Common Ancestor ◽  
Phylogenetic Divergence

Here we present a comparison of saddle and eye patch patterns of killer whales from Norwegian, Icelandic, British, Spanish and Greenlandic waters. We found only a small amount of variation in saddle patch shapes, which may reflect a recent phylogenetic divergence from the most recent common ancestor. Eye patch shapes were more variable than saddle patches in small details. Most individuals had eye patches with parallel orientation, with the exception of a small group of killer whales from the Hebrides, which, as previously reported, had sloping eye patches that sloped downward at the posterior end. This differentiation in pigmentation patterns of the Hebridean killer whales from neighbouring populations could reflect one or more of several evolutionary processes, including a deeper phylogenetic divergence, low gene flow with other local populations and drift.

Sex hormone concentrations in blood serum from the North Atlantic fin whale (Balaenoptera physalus)

1992 ◽  
Vol 134 (3) ◽  
pp. 405-413 ◽  
Author(s):  
J. M. Kjeld ◽  
J. Sigurjónsson ◽  
A. Árnason
Keyword(s):  
Blood Serum ◽  
Pregnancy Rate ◽  
Age Distribution ◽  
Balaenoptera Physalus ◽  
Serum Progesterone ◽  
Fin Whale ◽  
Pregnant Females ◽  
The North ◽  
Group I ◽  
Fin Whales

ABSTRACT Blood serum concentrations of testosterone and progesterone were measured in postmortem samples taken at sea from 814 fin whales (Balaenoptera physalus) caught during the summers (June–September) of 1981–1989. The ages of 781 of these animals were also assessed. The testosterone concentrations in samples from 352 males averaged 2 nmol/l; 41 samples had concentrations of 0·1 nmol/l or lower and 34 of these came from whales aged between 2 and 14 years and showed a Gaussian type of age distribution with a peak number at 7 to 8 years. The mean testosterone concentrations in the males increased by more than fourfold between June and August. Serum progesterone concentrations of the 462 females fell into three separate groups: (1) group I with values ≤ 0·1 nmol/l; (2) group II with intermediate values of > 0·1 nmol/l but <10 nmol/l; (3) group III with values of ≥ 10 nmol/l. These three groups of females seemed to consist respectively of young sexually immature females, mature non-pregnant females and pregnant females. The age distribution in the groups indicated that puberty in females is attained chiefly between the ages of 7 and 10. The yearly pregnancy rate (that percentage of all females caught and studied in a year which had progesterone values ≥10 nmol/l) was between 35% and 55%, except in 1987 when it was 67%. The yearly pregnancy rate would range from 56% to 93% if only mature females (i.e. those with serum progesterone >0·1 nmol/l) were considered. Serum oestradiol concentrations in male and female fin whales had no relation to age, sex or pregnancy. Journal of Endocrinology (1992) 134, 405–413

scholarly journals Ancient DNA from the extinct Haitian cave-rail ( Nesotrochis steganinos ) suggests a biogeographic connection between the Caribbean and Old World

2021 ◽  
Vol 17 (3) ◽  
Author(s):  
Jessica A. Oswald ◽  
Ryan S. Terrill ◽  
Brian J. Stucky ◽  
Michelle J. LeFebvre ◽  
David W. Steadman ◽  
...  
Keyword(s):  
Common Ancestor ◽  
Complete Mitochondrial Genome ◽  
Recent Common Ancestor ◽  
Evolutionary Relationships ◽  
Human Settlement ◽  
Comprehensive Understanding ◽  
The Holocene ◽  
Most Recent Common Ancestor ◽  
Extant Species ◽  
The Caribbean

Worldwide decline in biodiversity during the Holocene has impeded a comprehensive understanding of pre-human biodiversity and biogeography. This is especially true on islands, because many recently extinct island taxa were morphologically unique, complicating assessment of their evolutionary relationships using morphology alone. The Caribbean remains an avian hotspot but was more diverse before human arrival in the Holocene. Among the recently extinct lineages is the enigmatic genus Nesotrochis, comprising three flightless species. Based on morphology, Nesotrochis has been considered an aberrant rail (Rallidae) or related to flufftails (Sarothruridae). We recovered a nearly complete mitochondrial genome of Nesotrochis steganinos from fossils, discovering that it is not a rallid but instead is sister to Sarothruridae, volant birds now restricted to Africa and New Guinea, and the recently extinct, flightless Aptornithidae of New Zealand. This result suggests a widespread or highly dispersive most recent common ancestor of the group. Prior to human settlement, the Caribbean avifauna had a far more cosmopolitan origin than is evident from extant species.

Sign in / Sign up

Export Citation Format

Share Document