Showing posts sorted by date for query PATAGONIA. Sort by relevance Show all posts
Showing posts sorted by date for query PATAGONIA. Sort by relevance Show all posts

Sunday, October 04, 2026

 

How New World blackbirds conquered the Americas




University of Würzburg
Blackbirds

image: 

Three representatives of the more than 100 species (from left to right): the long-tailed grackle, the Baltimore oriole (mural by Brett Whitacre) and the Eastern Meadowlark. 

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Credit: Axel Arango







Where did the roughly 100 species of New World blackbirds alive today originate, and how did they spread across the Americas? 


Dr. Axel Arango Garcia and Professor Chaitanya S. Gokhale from the Chair for Computational and Theoretical Biology (CCTB) at Julius-Maximilians-Universität Würzburg (JMU) have reconstructed the evolutionary history of this family of birds. Their findings show that the ancestors of today’s species most likely originated in North America and gradually spread southwards over millions of years. The study has been published in the journal Frontiers of Biogeography.

The New World blackbirds – scientifically known as “Icteridae” – are a family of more than a hundred species of songbirds that can be found from Alaska to Tierra de Fuego. Famous members include orioles, grackles and cowbirds, and together they occupy nearly every habitat in the Americas, from the Arctic taiga to the tropical rainforest.

Despite a rich history of ecological, behavioural, and evolutionary studies, the origin of icterids and their biogeographic history has been debated for decades. In 1946, ornithologist Ernst Mayr proposed that icterids originated in South America and spread north in a stepwise manner. In 2015, a study by Barker et al. challenged this hypothesis though. Pointing instead to a North American origin. However, the study left open how and when the birds later spread across the Americas.


Step by step southwards

For their study, the researchers combined distribution data and evolutionary trees for 104 of the 106 currently recognised species. Using a range of statistical models, they reconstructed when and by which routes their ancestors spread across the Americas.

The scenario that best fits the data is one of stepwise southward colonisation: around 7.5 million years ago, the birds reached Mesoamerica and the Caribbean, followed by Amazonia around 6.1 million years ago and the Andes shortly afterwards. Southern South America followed around 4.8 million years ago, with Patagonia reached around 2.7 million years ago. These dates closely reflect the sequence reconstructed in the original study.

“Our findings trace the spread of New World blackbirds across the Americas as a long, gradual process. What is particularly interesting is that their ancestors appear to have reached South America before the present-day Isthmus of Panama had fully formed,” says Arango Garcia.

In South America earlier than previously thought

According to the model, the first dispersal into South America occurred around six million years ago – roughly three million years earlier than previous studies had suggested for this group of birds.

At that time, the present-day Isthmus of Panama had not yet fully formed. The birds may therefore have reached South America by crossing stretches of open water or via existing islands and land connections. At around the same time, open, grass-dominated habitats were expanding in South America. The scientific paper similarly discusses overwater dispersal or pre- or proto-isthmian land connections as possible routes.

“The spread of icterids into South America seem to coincide with the expansion of open, grass-dominated habitats there. It is therefore possible that the birds followed these suitable habitats southwards,” says Axel Arango.

The study cannot, however, demonstrate that these environmental changes actually caused the birds’ southward expansion.

New species mainly evolved locally

The analysis also shows that the colonisation of new regions alone does not explain why new species evolved. Instead, many species arose within regions that had already been colonised. The calculated rates of speciation were broadly similar in North and South America.

Which factors influenced the emergence of new species remains an open question. The authors point, for example, to specialisation in particular foods and habitats, social behaviour, or mate choice. Future studies could incorporate such traits directly into the models, allowing researchers to investigate more precisely why some evolutionary lineages produced more new species than others. This reflects the paper’s conclusion that factors other than geography – potentially including ecological specialisation, social behaviour, and sexual selection – are likely to play an important role in diversification.

Rooted in the classroom

This project has roots in the classroom. Arango has used Icteridae for years as a teaching example. In his classes, icterids have been the protagonists to illustrate macroecological rules, walk students through phylogenetic data analysis, and show how to manage phylogenetic information. The analysis behind this paper took shape while the researcher was preparing course material for a workshop on parametric biogeography, funded by a grant from the “Bayerische Hochschulzentrum für Lateinamerika” (BAYLAT). (https://www.baylat.org/)

“Even after years of working with icterids, it was still striking to discover that their lineages reached South America long before the land bridge closed, and to trace the exact dispersal routes they used to spread all the way to Tierra del Fuego,” says Axel Arango.

Saturday, September 26, 2026

Dozens of dead baby whales wash up on Argentina's coast

25.09.2026, DPA

Photo: -/Jordana Ibanez/dpa

Dozens of whale calves have washed up dead on beaches along Argentina's Valdés Peninsula, officials said.

A bacterial infection is currently considered the most likely cause, the government of Chubut province said this week. The bacterium can cause systemic disease in southern right whale calves. No evidence of a human-caused factor has been found so far.

Provincial authorities are investigating the strandings in collaboration with scientists.

The affected animals are southern right whales (Eubalaena australis), which migrate to the coasts of Argentina, Brazil and Uruguay to breed and raise their young. Large numbers gather in the gulfs of northern Patagonia.

Mariano Coscarella, a scientist with Argentina's National Scientific and Technical Research Council (CONICET), told the newspaper Página 12 that the mortality rate was "fairly high."

Authorities cautioned, however, that right whales die every year and that the current deaths could also form part of natural population dynamics. Mortality can vary considerably between and even within breeding seasons.

A bacterial infection remains the main working hypothesis, with similar outbreaks having been observed elsewhere in the world.

Important habitat and UNESCO World Natural Heritage Site

The Valdés Peninsula in Northern Patagonia, covering some 4,000 square kilometres, is an important refuge for marine mammals. Thousands of sea lions, elephant seals and numerous species of whale come to the coastal waters during the breeding and rearing season. 

Two ocean currents converge there, creating nutrient-rich waters. The peninsula was designated a UNESCO World Natural Heritage Site in 1999.

Saturday, August 29, 2026

 

Argentina locks in $900M for pipeline to feed first large-scale LNG exports


Oil extraction at Vaca Muerta, Argentina. Stock image.

Argentina’s San Matias Pipeline consortium said on Friday it had closed a $900 million project finance loan to build a pipeline from the Vaca Muerta shale formation to the Atlantic coast in Rio Negro province, a crucial piece of financing for the nation’s long-delayed ambition to become a global natural gas exporter.

The financing marks a major milestone for a country trying to turn one of the world’s largest unconventional gas reserves into hard-currency export revenue.

The 472-km (293-mile) pipeline will carry gas from Vaca Muerta – Argentina’s vast shale play in Patagonia – to floating liquefied natural gas vessels planned for the Gulf of San Matias.

The consortium behind the pipeline includes Pan American Energy, YPF, Pampa Energia, Harbour Energy and Golar LNG. It said the total project will cost about $1.3 billion, with the remaining roughly $400 million to be funded by the shareholders.

The seven-year loan was structured by Citi, J.P. Morgan, Santander and Itau, with BBVA, Bladex, Barclays, ICBC and Bank of China also joining the banking syndicate.

Construction is due to start in August 2026 and finish by mid-2028, according to the group. The 36-inch pipeline will have capacity to transport 27 million cubic meters of gas per day, enough to supply two floating LNG plants being developed by Southern Energy, a separate consortium with the same ownership group.

Those vessels – the Hilli Episeyo, due to begin operating in 2027, and the Esperanza, expected in 2028 – are planned to produce a combined 6 million metric tons per year of LNG. The expected shipments would mark Argentina’s return to large-scale LNG exports.

(Reporting by Kylie Madry and Nicolas Misculin)

Tuesday, July 07, 2026

 

South32’s Arizona $2 billion zinc and manganese mine to get US approval


The Hermosa project in Arizona. Reference (Image courtesy of South32.)

The Trump administration is set to authorize South32 Ltd.’s planned $2 billion zinc and manganese mine in Arizona on Tuesday.

The Agriculture Deprtment’s US Forest Service plans to issue a record of decision greenlighting the project near the Mexico border after the Trump administration gave it fast-track permitting, according to a statement from the agency seen by Bloomberg. The project was the first mining project to win expedited treatment from the Agriculture Department, after the Federal Permitting Improvement Steering Council designated it for swift review.

The critical minerals project contains one of the world’s largest undeveloped zinc deposits as well as other key minerals essential for steel and the production of large-capacity batteries, the Agriculture Department said. 


The fast-track approval dovetails with President Donald Trump’s second-term goal of boosting US supply chains and lessening the country’s reliance on China for critical minerals that are essential to manufacturing consumer goods and advanced energy technology.

“The Hermosa Critical Minerals Project shows how increasing domestic production can reduce our dependence on vulnerable foreign sources, and power modern industries, advanced technologies, and essential infrastructure,” Agriculture Secretary Brooke Rollins said in a statement. 

Australia-based South32 has said the mine, located in the Patagonia Mountains about 80 kilometers (50 miles) southeast of Tucson, Arizona, will reach full production by 2029.

Under its expedited review, the mine is securing approval two months ahead of a deadline under federal environmental law. That demonstrates the Trump administration’s commitment to to getting these projects online responsibly and quickly, the Agriculture Department said. The project was first nominated for fast-track consideration under former President Joe Biden.

South32 is aiming to prioritize domestic and regional smelters for copper extracted from the site. Currently, China dominates the world’s zinc smelting capacity, and the US depends heavily on imports of processed metal.

Saturday, July 04, 2026