Ana M. Valenzuela-Toro

• PhD
• Research Assistant at CIAHN Atacama

Latin American aquatic mammal fossils offer key insights into the evolution of life in the Southern Hemisphere. However, many fossils are housed in Global North institutions and are studied by overseas researchers. Latin American women researchers also face gender bias that undermines their ability to study fossils, publish, and gain peer recogniti...

Al oeste de la localidad La Cueva (34°S) afloran estratos de conglomerados y areniscas correspondientes a For-mación La Cueva que sobreyacen conglomerados pertenecientes a Fm. Rapel. Esta unidad presenta una edad acotada pliocena, datada previamente según moluscos marinos y radiometría en clastos de pumitas y escorias presentes en la sucesión sedim...

La Bahía de Carrizalillo, al sur de Chañaral de Aceituno en la Comuna de Freirina, Región de Atacama, es una localidad clásica de la Formación Coquimbo. Pese a que la presencia de abundantes restos fósiles en el área ha sido mencionada desde finales del siglo XIX, a la fecha solo existen menciones de restos de vertebrados de estos estratos, que de...

La Formación Bahía Inglesa (FBI), en la región de Atacama, corresponde a una sucesión marina de edad comprendida entre el Mioceno medio y el Pleistoceno inferior en la que se han registrado abundantes fósiles de vertebrados marinos, incluyendo elasmobranquios, teleósteos, gaviales, aves y mamíferos marinos, entre otros. La correlación estratigráfic...

The modern marine megafauna is known to play important ecological roles and includes many charismatic species that have drawn the attention of both the scientific community and the public. However, the extinct marine megafauna has never been assessed as a whole, nor has it been defined in deep time. Here, we review the literature to define and list...

Many marine mammal populations are recovering after long eras of exploitation.1,2 To what degree density-dependent body size declines in recovering species reflect a general response to increased resource competition is unknown. We examined skull size (as a proxy for body size), skull morphology, and foraging dynamics of the top marine predator, th...

Body size and feeding morphology influence how animals partition themselves within communities. We tested the relationships among sex, body size, skull morphology and foraging in sympatric otariids (eared seals) from the eastern North Pacific Ocean, the most diverse otariid community in the world. We recorded skull measurements and stable carbon (δ...

Records of aquatic mammal fossils (e.g. cetaceans, pinnipeds, sirenians, mustelids, and desmostylians) from Latin America (Mexico to Tierra del Fuego, including Antartica) span since the mid-1800s. Aquatic mammal fossils received little attention from the scientific community, with most of the first studies conducted by Northern Hemisphere research...

Desmostylia is an extinct clade of marine mammals with two major sub-clades, Desmostylidae and Paleoparadoxiidae, known from Oligocene to Miocene strata of the North Pacific coastline. Within Paleoparadoxiidae, three genera have been identified: Archaeoparadoxia, Paleoparadoxia, and Neoparadoxia. The latter taxon is the geochronologically youngest...

Desmostylia is an extinct clade of marine mammals with two major sub-clades, Desmostylidae and Paleoparadoxiidae, known from Oligocene to Miocene strata of the North Paci c coastline. Within Paleoparadoxiidae, three genera have been identi ed: Archaeoparadoxia, Paleoparadoxia, and Neoparadoxia. The latter taxon is the geochronologically youngest pa...

The fossil record of marine mammals from the upper Pliocene of the western coast of South America is poorly known, hindering our knowledge about how and when marine mammal faunas attained their modern distribution in the area. Here, we describe a new marine mammal assemblage from the Horcón Formation (upper Pliocene), located in the Valparaíso Regi...

It’s time to tackle the cumulative barriers and biases faced by scientists who aren’t from wealthy countries. It’s time to tackle the cumulative barriers and biases faced by scientists who aren’t from wealthy countries.

Racial and ethnic discrimination persist in science, technology, engineering and mathematics fields, including ecology, evolution and conservation biology (EECB) and related disciplines. Marginalization and oppression as a result of institutional and structural racism continue to create barriers to inclusion for Black people, Indigenous people and...

Otariids exhibit a semiaquatic lifestyle, feeding in the water and breeding and resting on land. Fur seals and sea lions, the two groups of otariids, exhibit an overall income breeding system where the females alternate between trips to the foraging grounds and periods at the breeding colony to feed the pup. How far and how long lactating females c...

Elephant seals ( Mirounga spp.) are the largest living pinnipeds, and the spatial scales of their ecology, with dives over 1 km in depth and foraging trips over 10,000 km long, are unrivalled by their near relatives. Here we report the discovery of an incomplete Holocene age Southern elephant seal ( M. leonina ) rostrum from Indiana, USA. The survi...

The fossil record of pinnipeds (seals, fur seals and walruses) is globally distributed, spanning from the late Oligocene to the Holocene. This record shows a complex evolutionary history that could not otherwise be inferred from their extant relatives, including multiple radiations and iterative ecomorphological specializations among different line...

True seals (crown Phocidae) originated during the late Oligocene-early Miocene (approx. 27-20 Ma) in the North Atlantic/Mediterranean region, with later (middle Miocene, approx. 16-11 Ma) dispersal events to the South Atlantic and South Pacific. Contrasting with other pinnipeds, the fossil record of phocids from the North Pacific region is scarce a...

While large mass mortality events (MMEs) are well known for toothed whales, they have been rare in baleen whales due to their less gregarious behaviour. Although in most cases the cause of mortality has not been conclusively identified, some baleen whale mortality events have been linked to bio-oceanographic conditions, such as harmful algal blooms...

National Fisheries Service cruise report.

While large mass mortality events (MMEs) are well known for toothed whales, they have been rare in baleen whales due to their less gregarious behaviour. Although in most cases the cause of mortality has not been conclusively identified, some baleen whale mortality events have been linked to bio-oceanographic conditions, such as harmful algal blooms...

While large mass mortality events (MMEs) are well known for toothed whales, they have been rare in baleen whales due to their less gregarious behaviour. Although in most cases the cause of mortality has not been conclusively identified, some baleen whale mortality events have been linked to bio-oceanographic conditions, such as harmful algal blooms...

While large mass mortality events (MMEs) are well known for toothed whales, they have been rare in baleen whales due to their less gregarious behaviour. Although in most cases the cause of mortality has not been conclusively identified, some baleen whale mortality events have been linked to bio-oceanographic conditions, such as harmful algal blooms...

Along the south-western coast of South America, three genera of fossil phocids (true seals) have been formally described from the late Neogene: Acrophoca and Piscophoca from Chile and Peru, and, more recently, Hadrokirus from Peru, which all represent medium- to large-sized phocids. Here, we report the discovery of Australophoca changorum gen. et s...

The genus Mirounga is the largest living member of the Phocidae family (true seals) and includes two species: M. angustirostris and M. leonina. These species exhibit a noticeable antitropical distribution in the Northern and Southern hemispheres, respectively. The evolutionary history of elephant seals, especially in regard to establishing this ant...

Marine mammal mass strandings have occurred for millions of years, but their origins defy singular explanations. Beyond human causes, mass strandings have been attributed to herding behaviour, large-scale oceanographic fronts and harmful algal blooms (HABs). Because algal toxins cause organ failure in marine mammals, HABs are the most common mass s...

Modern pinnipeds distributed along the coasts of continental South America consist almost entirely of otariids (sea lions and fur seals). In contrast, phocids (true seals) are present only on the southernmost extreme of Chile. This recent biogeographic pattern is consistent with the zooarchaeological record (∼8—2 ka), but it is incompatible with th...