A quantitative test of the "Ecomorphotype Hypothesis" for fossil true seals (Family Phocidae).

The fossil record of true seals (Family Phocidae) is mostly made up of isolated bones, some of which are type specimens. Previous studies have sought to increase referral of non-overlapping and unrelated fossils to these taxa using the 'Ecomorphotype Hypothesis', which stipulates that certain differences in morphology between taxa represent adaptations to differing ecology. On this basis, bulk fossil material could be lumped to a specific ecomorphotype, and then referred to species in that ecomorphotype, even if they are different bones. This qualitative and subjective method has been used often to expand the taxonomy of fossil phocids, but has never been quantitatively tested. We test the proposed ecomorphotypes using morphometric analysis of fossil and extant northern true seal limb bones, specifically principal components analysis and discriminant function analysis. A large amount of morphological overlap between ecomorphotypes, and poor discrimination between them, suggests that the 'Ecomorphotype Hypothesis' is not a valid approach. Further, the analysis failed to assign fossils to ecomorphotypes designated in previous studies, with some fossils from the same taxa being designated as different ecomorphotypes. The failure of this approach suggests that all fossils referred using this method should be considered to have unknown taxonomic status. In light of this, and previous findings that phocid limb bones have limited utility as type specimens, we revise the status of named fossil phocid species. We conclude that the majority of named fossil phocid taxa should be considered nomina dubia.

Charting the Course of Pinniped Evolution: insights from molecular phylogeny and fossil record integration.

Pinnipeds (seals, sea lions, walruses, and their fossil relatives) are one of the most successful mammalian clades to live in the oceans. Despite a well-resolved molecular phylogeny and a global fossil record, a complete understanding of their macroevolutionary dynamics remains hampered by a lack of formal analyses that combine these two rich sources of information. We used a meta-analytic approach to infer the most densely sampled pinniped phylogeny to-date (36 recent and 93 fossil taxa) and used phylogenetic paleobiological methods to study their diversification dynamics and biogeographic history. Pinnipeds mostly diversified at constant rates. Walruses however experienced rapid turnover in which extinction rates ultimately exceeded speciation rates from 12-6 Ma, possibly due to changing sea-levels and/or competition with otariids (eared seals). Historical biogeographic analyses including fossil data allowed us to confidently identify the North Pacific and the North Atlantic (plus or minus Paratethys) as the ancestral ranges of Otarioidea (eared seals + walrus) and crown phocids (earless seals), respectively. Yet, despite the novel addition of stem pan-pinniped taxa, the region of origin for Pan-Pinnipedia remained ambiguous. These results suggest further avenues of study in pinnipeds and provide a framework for investigating other groups with substantial extinct and extant diversity.

Giant baleen whales emerged from a cold southern cradle.

Baleen whales (mysticetes) include the largest animals on the Earth. How they achieved such gigantic sizes remains debated, with previous research focusing primarily on when mysticetes became large, rather than where. Here, we describe an edentulous baleen whale fossil (21.12-16.39 mega annum (Ma)) from South Australia. With an estimated body length of 9 m, it is the largest mysticete from the Early Miocene. Analysing body size through time shows that ancient baleen whales from the Southern Hemisphere were larger than their northern counterparts. This pattern seemingly persists for much of the Cenozoic, even though southern specimens contribute only 19% to the global mysticete fossil record. Our findings contrast with previous ideas of a single abrupt shift towards larger size during the Plio-Pleistocene, which we here interpret as a glacially driven Northern Hemisphere phenomenon. Our results highlight the importance of incorporating Southern Hemisphere fossils into macroevolutionary patterns, especially in light of the high productivity of Southern Ocean environments.

True seals achieved global distribution by breaking Bergmann's rule.

True seals (phocids) have achieved a global distribution by crossing the equator multiple times in their evolutionary history. This is remarkable, as warm tropical waters are regarded as a barrier to marine mammal dispersal and-following Bergmann's rule-may have limited crossings to small-bodied species only. Here, we show that ancestral phocids were medium sized and did not obviously follow Bergmann's rule. Instead, they ranged across a broad spectrum of environmental temperatures, without undergoing shifts in temperature- or size-related evolutionary rates following dispersals across the equator. We conclude that the tropics have not constrained phocid biogeography.

First monk seal from the Southern Hemisphere rewrites the evolutionary history of true seals.

Living true seals (phocids) are the most widely dispersed semi-aquatic marine mammals, and comprise geographically separate northern (phocine) and southern (monachine) groups. Both are thought to have evolved in the North Atlantic, with only two monachine lineages-elephant seals and lobodontins-subsequently crossing the equator. The third and most basal monachine tribe, the monk seals, have hitherto been interpreted as exclusively northern and (sub)tropical throughout their entire history. Here, we describe a new species of extinct monk seal from the Pliocene of New Zealand, the first of its kind from the Southern Hemisphere, based on one of the best-preserved and richest samples of seal fossils worldwide. This unanticipated discovery reveals that all three monachine tribes once coexisted south of the equator, and forces a profound revision of their evolutionary history: rather than primarily diversifying in the North Atlantic, monachines largely evolved in the Southern Hemisphere, and from this southern cradle later reinvaded the north. Our results suggest that true seals crossed the equator over eight times in their history. Overall, they more than double the age of the north-south dichotomy characterizing living true seals and confirms a surprisingly recent major change in southern phocid diversity.

A new large-bodied Pliocene seal with unusual cutting teeth.

Today, monachine seals display the largest body sizes in pinnipeds. However, the evolution of larger body sizes has been difficult to assess due to the murky taxonomic status of fossil seals, including fossils referred to Callophoca obscura, a species thought to be present on both sides of the North Atlantic during the Neogene. Several studies have recently called into question the taxonomic validity of these fossils, especially those from the USA, as the fragmentary lectotype specimen from Belgium is of dubious diagnostic value. We find that the lectotype isolated humerus of C. obscura is too uninformative; thus, we designate C. obscura as a nomen dubium. More complete cranial and postcranial specimens from the Pliocene Yorktown Formation are described as a new taxon, Sarcodectes magnus. The cranial specimens display adaptations towards an enhanced ability to cut or chew prey that are unique within Phocidae, and estimates indicate S. magnus to be around 2.83 m in length. A parsimony phylogenetic analysis found S. magnus is a crown monachine. An ancestral state estimation of body length indicates that monachines did not have a remarkable size increase until the evolution of the lobodontins and miroungins.

How dentistry should approach its problems: a vote for professionalism.

Dentistry, like all professions, has always had ethical problems to contend with, including societal trust, flagrant advertising, commercialism, and access to care. Although the profession's interest and expertise in ethics has grown enormously in the last three decades, the issues facing dentistry have not really decreased, and perhaps have grown more problematic. Thus, despite the invaluable contributions of ethical progress to the structure and function of our profession, this paper argues that reflective ethics by itself appears unable to exact change. For change to occur, dentistry also needs a broad-based display of enlightened, and ethically-driven but action-oriented professionalism. This existed in the 1830s when U.S. dentistry was in its early stages of becoming thought of as a profession. Using the lessons learned from that period of our history, we need to do the same thing now--not excluding ethics, but working hand in glove with ethics. This paper suggests that, as in the 1830s, dentistry now needs the grassroots attention of its membership. Using recent publications about the importance of "connectedness" in dentistry, guidelines are presented that provide a framework for approaching the problems faced by dentistry and contributing to a more satisfying professional career.

The dilemma of access to care: symptom of a systemic condition.

The standard ethical arguments that prescribe dentistry's involvement in improving access to oral health care are based on the ethical principle of social justice. The authors underwrite this principle but argue that, as with other ethical principles, this principle alone will fail to have a practical impact. The authors show that the issue of access is a symptom of a more systemic problem in dentistry, namely the lack of connectedness that dentists feel between themselves and their profession, their community, and society at large. The second half of the article develops a plan for boosting "connectedness." Successful implementation should help resolve many of the systemic problems that dentistry currently faces, including the issue of disparities in oral health.

Hugo A. Owens: dentist, civil rights leader, politician.

For 44 years Dr. Hugo A. Owens was a distinguished practitioner and community leader in Portsmouth, Virginia. Besides his affinity to for dentistry, he was driven by two other passions: politics and civil rights. In 1970 he was one of the first African-Americans elected to the Portsmouth City Council. He was reelected for the next term and appointed Vice Mayor, a position he held for eight years. His political successes were preceded by his activities as a civil rights leader, which began in 1950 and lasted through the 1960s. In a remarkable series of negotiations and litigations, Dr. Owens was the prime mover in the desegregation of the City of Portsmouth. In all three 'careers, Dr. Owens used dentistry as a home base for the expression of his activist philosophy of providing help for others when they were unable to do things for themselves.

Organized dentistry as an agent for helping others: the leadership of Donna J. Rumberger.

Dr Donna Rumberger graduated from New York University College of Dentistry in 1980 and has practiced dentistry in Manhattan ever since. Even before her graduation, she was active in organized dentistry, always viewing it as a conduit for helping other people. Working with the American Association of Women Dentists, she was cofounder of the Smiles for Success Foundation, a program started in New York City that helps women advance from welfare into the workforce with restored, healthy smiles. That program now has expanded to 14 other cities. Working with organized dentistry in New York City, she has been instrumental in initiating and running the Skate Safe program, which provides mouthguards and oral home care education for inner city children in Harlem. In addition, she has worked with the dentistry merit badge program for the Boy Scouts of America Jamborees, helped coalesce women's dental organizations in New York City, and led her dental society to collaborate with Columbia University in a program to improve access to dental care. As further evidence of her ability to get things done, she also has served as president of the American Association of Women Dentists, the Midtown Dental Society, and the New York County Dental Society--one of the largest dental societies in the country.

Serving the poorest of the poor: the story of Jeremiah J. Lowney.

Since 1966, Dr Jerry Lowney has practiced orthodontics in Norwich, Connecticut, where he has been active in both community and professional organizations, including the University of Connecticut Board of Trustees and the Board of Governors for Higher Education. Since his first volunteer trip to Haiti in the mid-1980s, during which he provided dental services for the poor, he has returned to that country at least three times each year. Over time the nature of his activities has changed. Through grant writing, personal influence, liaison with a religious order, a huge investment of time, successful fundraising, the seizing of every opportunity, and the expenditure of large amounts of his own money, he has created a multimillion-dollar general health facility in one of the poorest areas in Haiti. Besides dental treatment, the scope of his activities has ranged from creating centers for high-risk pregnancy and malnutrition to the hiring of physicians, the training of local nurse practitioners, and an Adopt-a-Family program run by his wife, Virginia. His actions have been influenced by Virginia's caring attitudes and by his conviction that much is expected from those who have received life's bounties.