scholarly journals A Miocene pygmy right whale fossil from Australia

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5025 ◽  
Author(s):  
Felix G. Marx ◽  
Travis Park ◽  
Erich M.G. Fitzgerald ◽  
Alistair R. Evans
Keyword(s):  
Southern Hemisphere ◽  
Late Miocene ◽  
External Morphology ◽  
Baleen Whales ◽  
Right Whale ◽  
Right Whales ◽  
Molecular Divergence ◽  
Living Species ◽  
Divergence Estimates ◽  
Single Living

Neobalaenines are an enigmatic group of baleen whales represented today by a single living species: the pygmy right whale, Caperea marginata, found only in the Southern Hemisphere. Molecular divergence estimates date the origin of pygmy right whales to 22–26 Ma, yet so far there are only three confirmed fossil occurrences. Here, we describe an isolated periotic from the latest Miocene of Victoria (Australia). The new fossil shows all the hallmarks of Caperea, making it the second-oldest described neobalaenine, and the oldest record of the genus. Overall, the new specimen resembles C. marginata in its external morphology and details of the cochlea, but is more archaic in it having a hypertrophied suprameatal area and a greater number of cochlear turns. The presence of Caperea in Australian waters during the Late Miocene matches the distribution of the living species, and supports a southern origin for pygmy right whales.

scholarly journals Evidence that ship noise increases stress in right whales

2012 ◽  
Vol 279 (1737) ◽  
pp. 2363-2368 ◽  
Author(s):  
Rosalind M. Rolland ◽  
Susan E. Parks ◽  
Kathleen E. Hunt ◽  
Manuel Castellote ◽  
Peter J. Corkeron ◽  
...  
Keyword(s):  
Low Frequency ◽  
Acoustic Signals ◽  
Frequency Noise ◽  
Underwater Noise ◽  
Baleen Whales ◽  
Ship Traffic ◽  
Right Whale ◽  
Right Whales ◽  
North Atlantic Right Whales ◽  
Shipping Traffic

Baleen whales ( Mysticeti ) communicate using low-frequency acoustic signals. These long-wavelength sounds can be detected over hundreds of kilometres, potentially allowing contact over large distances. Low-frequency noise from large ships (20–200 Hz) overlaps acoustic signals used by baleen whales, and increased levels of underwater noise have been documented in areas with high shipping traffic. Reported responses of whales to increased noise include: habitat displacement, behavioural changes and alterations in the intensity, frequency and intervals of calls. However, it has been unclear whether exposure to noise results in physiological responses that may lead to significant consequences for individuals or populations. Here, we show that reduced ship traffic in the Bay of Fundy, Canada, following the events of 11 September 2001, resulted in a 6 dB decrease in underwater noise with a significant reduction below 150 Hz. This noise reduction was associated with decreased baseline levels of stress-related faecal hormone metabolites (glucocorticoids) in North Atlantic right whales ( Eubalaena glacialis ). This is the first evidence that exposure to low-frequency ship noise may be associated with chronic stress in whales, and has implications for all baleen whales in heavy ship traffic areas, and for recovery of this endangered right whale population.

scholarly journals The pygmy right whale Caperea marginata : the last of the cetotheres

2013 ◽  
Vol 280 (1753) ◽  
pp. 20122645 ◽  
Author(s):  
R. Ewan Fordyce ◽  
Felix G. Marx
Keyword(s):  
Morphological Characters ◽  
Total Evidence ◽  
Baleen Whales ◽  
Virtual Absence ◽  
Right Whale ◽  
Morphological Studies ◽  
Wide Range ◽  
Evolutionary Context ◽  
Living Species ◽  
Cladistic Analyses

The pygmy right whale, Caperea marginata , is the most enigmatic of the living baleen whales (Mysticeti). Its highly disparate morphology and the virtual absence of a described fossil record have made it extremely difficult to place Caperea into a broader evolutionary context, and molecular and morphological studies have frequently contradicted each other as to the origins and phylogenetic relationships of the species. Our study of a wealth of material from New Zealand collections, representing a wide range of ontogenetic stages, has identified several new features previously unreported in Caperea , which suggest that the pygmy right whale may be the last survivor of the supposedly extinct family Cetotheriidae. This hypothesis is corroborated by both morphology-based and total evidence cladistic analyses, including 166 morphological characters and 23 taxa, representing all the living and extinct families of toothless baleen whales. Our results allow us to formally refer Caperea to Cetotheriidae, thus resurrecting the latter from extinction and helping to clarify the origins of a long-problematic living species.

The Use of Ecological Tolerances for the Reconstruction of Tertiary Palaeoclimates

1997 ◽  
Vol 45 (3) ◽  
pp. 475 ◽  
Author(s):  
Helene A. Martin
Keyword(s):  
Vegetation Types ◽  
Climatic Parameters ◽  
Salt Tolerant ◽  
Pollen Assemblage ◽  
Pollen Types ◽  
Living Species ◽  
Marine Influence ◽  
Lagarostrobos Franklinii ◽  
Single Living ◽  
Very High

The major vegetation types may be recognised from the pollen assemblage being deposited beneath them, hence the palaeovegetation may be reconstructed from fossil pollen assemblages. The climatic parameters of the vegetation may then be used to reconstruct palaeoclimates. The result, however, is very general. Most pollen types can only be affiliated with a family, a genus or a group of species and the ecological tolerances within these groups may not be uniform. There are, however, some distinctive pollen types that can be identified with a single living species and this paper examines the potential of these types in the reconstruction of palaeoclimates. Lagarostrobos franklinii (J.D.Hook) Quinn, Huon pine, has a long history and the fossil occurrences of it are compatible with the hypothesis that its ecological tolerances have not changed and it has always required very high humidity. Two sclerophyllous taxa,Eucalyptus spathulata Hook. and Dodonaea triquetra Wendl., however, coexisted with rainforest and then other vegetation types as the climate became drier, adapting to the prevailing conditions. The evidence suggests that the salt-tolerant E. spathulata may have evolved in small patches of coastal scrub, subjected to marine influence, within the dominant rainforest vegetation.

Estimating mean body masses of marine mammals from maximum body lengths

1998 ◽  
Vol 76 (5) ◽  
pp. 886-896 ◽  
Author(s):  
Andrew W Trites ◽  
Daniel Pauly
Keyword(s):  
Marine Mammals ◽  
Growth Curves ◽  
Survival Models ◽  
Regression Equations ◽  
Sperm Whales ◽  
Baleen Whales ◽  
Sea Lions ◽  
Living Species ◽  
Maximum Body ◽  
Maximum Body Length

Generalized survival models were applied to growth curves published for 17 species of cetaceans (5 mysticetes, 12 odontocetes) and 13 species of pinnipeds (1 odobenid, 4 otariids, 8 phocids). The mean mass of all individuals in the population was calculated and plotted against the maximum body length reported for each species. The data showed strong linearity (on logarithmic scales), with three distinct clusters of points corresponding to the mysticetes (baleen whales), odontocetes (toothed whales), and pinnipeds (seals, sea lions, and walruses). Exceptions to this pattern were the sperm whales, which appeared to be more closely related to the mysticetes than to the odontocetes. Regression equations were applied to the maximum lengths reported for 76 species of marine mammals without published growth curves. Estimates of mean body mass were thus derived for 106 living species of marine mammals.

scholarly journals Flying rocks and flying clocks: disparity in fossil and molecular dates for birds

2014 ◽  
Vol 281 (1788) ◽  
pp. 20140677 ◽  
Author(s):  
Daniel T. Ksepka ◽  
Jessica L. Ware ◽  
Kristin S. Lamm
Keyword(s):  
Analytical Methods ◽  
Fossil Record ◽  
Tree Of Life ◽  
Temporal Information ◽  
Molecular Dating ◽  
Critical Nodes ◽  
Molecular Divergence ◽  
Divergence Dates ◽  
Divergence Estimates ◽  
Age Estimates

Major disparities are recognized between molecular divergence dates and fossil ages for critical nodes in the Tree of Life, but broad patterns and underlying drivers remain elusive. We harvested 458 molecular age estimates for the stem and crown divergences of 67 avian clades to explore empirical patterns between these alternate sources of temporal information. These divergence estimates were, on average, over twice the age of the oldest fossil in these clades. Mitochondrial studies yielded older ages than nuclear studies for the vast majority of clades. Unexpectedly, disparity between molecular estimates and the fossil record was higher for divergences within major clades (crown divergences) than divergences between major clades (stem divergences). Comparisons of dates from studies classed by analytical methods revealed few significant differences. Because true divergence ages can never be known with certainty, our study does not answer the question of whether fossil gaps or molecular dating error account for a greater proportion of observed disparity. However, empirical patterns observed here suggest systemic overestimates for shallow nodes in existing molecular divergence dates for birds. We discuss underlying biases that may drive these patterns.

Fishing-gear threat to right whales (Eubalaena glacialis) in Canadian waters and the risk of lethal entanglement

2011 ◽  
Vol 68 (12) ◽  
pp. 2174-2193 ◽  
Author(s):  
Angelia S.M. Vanderlaan ◽  
R. Kent Smedbol ◽  
Christopher T. Taggart
Keyword(s):  
Relative Risk ◽  
North Atlantic ◽  
Eubalaena Glacialis ◽  
Bay Of Fundy ◽  
Commercial Fishing ◽  
Fishing Gear ◽  
Critical Habitat ◽  
North Atlantic Right Whale ◽  
Right Whale ◽  
Right Whales

Commercial fishing gear can potentially entangle any whale, and this is especially true for the endangered North Atlantic right whale ( Eubalaena glacialis ), for which entanglement is second only to vessel strike as being responsible for documented right whale deaths. We use right whale survey data and Canadian fishing-gear deployment data to estimate the relative threat of gear entanglement in a Scotia–Fundy study area and the relative risk of lethal entanglement in the Bay of Fundy and on Roseway Basin, Scotian Shelf, where Critical Habitat has been legislated. We focus on groundfish and pelagic hook-and-line; groundfish gillnet; and crab-, hagfish-, and inshore and offshore lobster-trap gear. Our analyses demonstrate that groundfish hook-and-line gear poses the greatest threat to right whales among the seven gear types analysed during the summer-resident period in Critical Habitat and that gear from the lobster fisheries poses the greatest threat during the spring and autumn periods when whales are migrating to and from Critical Habitat. We suggest that area-specific seasonal closures of some fisheries would reduce threat and risk to whales without unduly compromising fishing interests.

scholarly journals Ancestor–descendant relationships in evolution: origin of the extant pygmy right whale, Caperea marginata

2015 ◽  
Vol 11 (1) ◽  
pp. 20140875 ◽  
Author(s):  
Cheng-Hsiu Tsai ◽  
R. Ewan Fordyce
Keyword(s):  
Punctuated Equilibrium ◽  
Fundamental Concept ◽  
Baleen Whales ◽  
Right Whale ◽  
Morphological Stasis

Ancestor–descendant relationships (ADRs), involving descent with modification, are the fundamental concept in evolution, but are usually difficult to recognize. We examined the cladistic relationship between the only reported fossil pygmy right whale, †Miocaperea pulchra , and its sole living relative, the enigmatic pygmy right whale Caperea marginata , the latter represented by both adult and juvenile specimens. †Miocaperea is phylogenetically bracketed between juvenile and adult Caperea marginata in morphologically based analyses, thus suggesting a possible ADR—the first so far identified within baleen whales (Cetacea: Mysticeti). The †Miocaperea–Caperea lineage may show long-term morphological stasis and, in turn, punctuated equilibrium.

Great Whales

2008 ◽  
Author(s):  
John Bannister
Keyword(s):  
Sperm Whale ◽  
Modern Technology ◽  
Current Status ◽  
Blue Whale ◽  
Baleen Whales ◽  
Fin Whale ◽  
Right Whale ◽  
Toothed Whale ◽  
History Of ◽  
Storey Building

Whales are mysterious and fascinating creatures. Despite modern technology, their world is still largely unexplored and unknown. They can only be seen, or rather glimpsed, when they are near the sea surface, either from boats, or perhaps from shore, or underwater by divers. They also reach astonishing sizes – the blue whale, for example, can grow to 30 metres in length, equivalent to the height of a six-storey building, and can weigh more than 130 tonnes. Seven ‘Great Whales’ are found in the coastal waters surrounding Australia. These include six of the largest baleen whales – blue whale, fin whale, humpback whale, sei whale, Bryde’s whale and southern right whale – and the sperm whale, the largest toothed whale. This book provides a detailed account of these extraordinary mammals. As well as the seven Great Whales, a smaller species – the minke whale – is included because of its special interest to Australians. The book describes whales’ highly specialised mammalian structure and biology, and the history of people’s association with them, at first through legend and wonder, then whaling, and more recently whale watching. It also looks at their past and current status, and the conservation initiatives that are in place to protect them from existing or potential threats. With both historical and recent photographs, as well as an extensive glossary, Great Whales will be enjoyed by natural history enthusiasts, zoologists and students alike.

Human Evolution

1984 ◽  
Vol 8 ◽  
pp. 182-198
Author(s):  
Catherine Badgley
Keyword(s):  
Human Evolution ◽  
Evolutionary History ◽  
Pan Paniscus ◽  
Homo Sapiens ◽  
Great Apes ◽  
Sister Group ◽  
The Family ◽  
History Of ◽  
Living Species ◽  
Single Living

The evolutionary history of humans is well understood in outline, compared to that of many other groups of mammals. But human evolution remains enigmatic in its details, and these are compelling both scientifically and personally because they relate to the biological uniqueness of humans. Humans are placed in the primate family Hominidae, which, in traditional classifications, contains a single living species, Homo sapiens. The closest living relatives of humans are great apes: the chimpanzees Pan paniscus and Pan troglodytes, the gorilla Gorilla gorilla, and the orangutan Pongo pygmaeus. These apes have traditionally been placed in the family Pongidae as the sister group of Hominidae. Living Hominidae and Pongidae, together with Hylobatidae (gibbons) comprise the modern representatives of the primate suborder Hominoidea.

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