INTERNACIONAL
Un fósil del tamaño de un ratón hallado en Mongolia podría cambiar lo que se cree sobre el origen de los mamíferos
Un fósil hallado en el desierto del Gobi oriental de Mongolia y descrito en Nature identificó a Tamirkhan balcarceli y cambió una idea aceptada durante décadas sobre la evolución de este grupo de vertebrados. El hallazgo mostró que los llamados “Conejos del Cretácico” no pertenecían al linaje de los mamíferos placentarios, sino a los zalambdalestoideos, un grupo distinto de formas tempranas.
Según Phys.org, el espécimen apareció en 2004 durante una expedición patrocinada por el American Museum of Natural History, y su estudio reunió a científicos de esa institución, Stony Brook University, la University of Arizona y Arcadia University.
Andres Giallombardo, autor principal del estudio, dijo a Phys.org que el hallazgo demuestra por qué el trabajo de campo sigue siendo indispensable para reconstruir la historia de la vida. También lo definió como el momento más emocionante de su carrera, porque se trató de una especie nueva conservada de forma tan completa que además resolvió un problema científico de larga data.
Tamirkhan balcarceli, hallado en el Gobi oriental de Mongolia, medía entre 15 y 18 centímetros de la cabeza a la cola. Tenía patas traseras alargadas que le daban un aspecto parecido al de un conejo, una comparación informal que los paleontólogos han usado para referirse a estos animales.
El fósil conservó dientes bajos y redondeados, característicos de los zheléstidos, y también incisivos largos de crecimiento continuo. Sumó además varios rasgos del cráneo propios de los zalambdalestoideos, un grupo de pequeños mamíferos insectívoros parecidos a musarañas.
Shawn Zack, paleontólogo de la University of Arizona, afirmó a Phys.org que las patas traseras y los tobillos de Tamirkhan corresponden de forma inequívoca a los zalambdalestoideos. A partir de ese conjunto anatómico, los autores concluyeron que los zheléstidos no eran mamíferos placentarios ni especialmente parecidos a ellos.
Los zheléstidos se conocían desde hacía casi 40 años por dientes aislados y restos fragmentarios. Esas piezas, más especializadas para comer plantas que los dientes afilados de muchos mamíferos del Cretácico, llevaron a proponer que formaban un grupo desconocido.
Durante años se discutió si eran ejemplos de mamíferos placentarios del Cretácico o una línea separada que había adquirido rasgos parecidos por evolución independiente. La hipótesis de placentarios en ese período contaba con apoyo de modelos de reloj molecular, pero el nuevo fósil aportó pruebas en sentido contrario.
Paul Velazco, biólogo comparativo de Arcadia University, señaló a Phys.org que los modelos moleculares construidos a partir de animales vivos pueden anticipar el pasado, mientras los fósiles permiten comprobar esas predicciones.
Maureen O’Leary, paleontóloga de Stony Brook University e investigadora asociada del museo, subrayó en el mismo medio que un diente sigue siendo un fósil muy informativo, aunque no siempre alcanza para reconstruir al animal entero.
El espécimen también reforzó el valor científico del Gobi, uno de los pocos lugares donde se preservan zheléstidos junto con yacimientos de Kazajistán, Kirguistán y Uzbekistán.
Michael Novacek, curador de la División de Paleontología del museo, dijo a Phys.org que esa región es una de las escasas zonas donde aparecen con regularidad mamíferos del Cretácico tan completos.
Las conclusiones evolutivas del estudio también se apoyaron en MorphoBank, una plataforma filogenética publicada por primera vez en 2013. Esa base de datos se amplió durante más de una década con un número creciente de especies fósiles y sirvió como marco para analizar relaciones entre mamíferos tempranos.
El caso de Tamirkhan dejó una advertencia metodológica. Un diente puede orientar una clasificación, pero no basta por sí solo para fijar el retrato completo de un animal extinguido.
fósil,cráneo,mandíbula,paleontología,museo,exhibición
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FIRST ON FOX: As the White House touts «collapsing» violent crime rates in the U.S., the Department of Homeland Security is pointing to the deportation of violent criminal illegal immigrants as the «common sense» reason.
A new analysis by the Council on Criminal Justice (CCJ) released this month reported that homicides will «likely» reach a «new historic low» in the U.S. as most crime rates continue to decline mid-year. CCJ reported that homicides in a sample group of large U.S. cities are down 18% from the previous year, which is on pace for the lowest level since 1900. Additionally, carjackings are down 47%; motor vehicle thefts are down 20%; robberies are down 17% and residential burglaries are down 13%.
The White House touted the report as evidencing «extraordinary progress» in «delivering on one of President Trump’s core promises to restore law and order.»
Assistant DHS Secretary Lauren Bis told Fox News Digital, «It is common sense. When you remove criminals from the country, crime rates fall.»
ICE LODGES DETAINER FOR ILLEGAL IMMIGRANT ACCUSED OF TRYING TO DISARM VIRGINIA POLICE OFFICER
President Donald Trump announces the Freedom Haulers initiative on West Executive Avenue in Washington, D.C., on July 30, 2026. The program will allow military veterans to get expedited commercial driver’s licenses for trucking careers. The nation faces a shortage of truckers after licenses were stripped from immigrants who failed English language tests. (Andrew Harnik/Getty Images)
The agency shared exclusively with Fox News Digital some of the «worst of the worst» criminal illegal immigrants who have been deported just in the last few weeks. Recent deportees include foreign nationals convicted of homicide, drug trafficking, aggravated assault, carjacking and other crimes, in addition to multiple with illegal re-entries into the country.
Among those deported was a member of the foreign terrorist organization Tren de Aragua, a Honduran national named Jared Adonay Cruz-Rivera, according to DHS. He was deported on July 18 following a previous conviction for robbery and an arrest on charges of drug possession.
DHS said that one deportee, Olegario Ramirez, a Mexican national and Paisas gang member, has a criminal history including convictions for homicide and illegal re-entry into the U.S. He was deported on July 27.
Another Mexican national deported the same day was Bulmaro Rendon-Ramos, a Surenos gang member, who had convictions for robbery, burglary and four counts of driving under the influence of liquor.
ICE ARRESTS ILLEGAL IMMIGRANT ILLINOIS TEACHER LINKED TO TREN DE ARAGUA MASS SHOOTING
Mugshots, left to right from top: Jared Adonay Cruz-Rivera, Olegario Ramirez, Bulmaro Rendon-Ramos, Nammoun Khampanya, Omar Loaces Gonzalez, Marc James Guerrier Pinard. (Blake Fagan / AFP via Getty Images; DHS)
Nammoun Khampanya, a Crips gang member from Laos, was deported on July 28 following convictions for cocaine possession, possession of a weapon, obstructing police and fraud.
A Cuban national, Omar Loaces Gonzalez, was deported on July 17. His criminal history includes convictions for vehicle theft and wire fraud.
Additionally, Haitian national Marc James Guerrier Pinard was deported on July 16 following his convictions for three counts of armed carjacking and an arrest on charges of burglary.
NEW YORK TIMES TORCHED FOR ‘FALSE’ REPORTING ON ICE INVESTIGATIONS, OUTLET FIRES BACK
Federal agents are seen walking in uniform. A report from The New York Times said the Trump administration has lost or abandoned hundreds of cases in which it accused anti-ICE protesters and migrants of assaulting federal immigration agents. (John Moore/Getty Images)
Commenting on the deportations, Bis told Fox News Digital that «President Trump promised to make America safe again, and he has done just that.»
«Crime has fallen to record lows under the Trump administration, including murders on pace to drop to the lowest level in 126 years. It’s no surprise that this drop in crime coincides with deportations of dangerous criminal illegal aliens,» she said.
deportation, illegal immigrants, immigration, enforcement, homeland security, donald trump, migrant crime
INTERNACIONAL
Crisis migratoria en España: dudas y un opaco trasfondo político detrás del aluvión de marroquíes en Ceuta
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Francesca Hong, the likely Democratic nominee for governor in Wisconsin backed by the Democratic Socialists of America, once argued that Americans should not celebrate Thanksgiving.
«Cancel Thanksgiving. Should have done this in 1621,» Hong wrote in a now-deleted post to X.
«If it takes a worldwide pandemic for us to realize we should stop celebrating colonialism and the original superspreader event that killed indigenous folx [sic] and women, so be it,» she added, referring to the spread of smallpox that killed many indigenous Americans.
WISCONSIN DEM SOCIALIST GUBERNATORIAL HOPEFUL DODGES WHETHER SHE STILL WANTS TO ‘ABOLISH POLICE’
Governor candidate Francesca Hong speaks on stage during the Wisconsin Democrats 2026 Convention on June 14, 2026, in Madison, Wis. (Getty Images for WisDems)
The post, which was originally made in November 2020, sheds more light on Hong’s progressive thinking as she emerges as a frontrunner in the Wisconsin gubernatorial contest and drew mockery online.
«‘Folx,’» Stephen Miller, a conservative podcaster, posted to X, noting the term used to signal inclusivity of LGBTQ+ and other marginalized groups.
«Francesca Hong is all but certain to be the Democratic nominee for governor of Wisconsin. She also wants to ‘Cancel Thanksgiving,’ according to a since-deleted tweet. What is going on in Wisconsin??» another observer wrote.
Hong has leaned into her socialist record in her campaign, describing it as ensuring that «working-class people have their fair share.»
Hong shares policy positions with other notable progressives like New York Mayor Zohran Mamdani, another self-proclaimed socialist. Among other platform positions, Hong is championing race-based grants for social workers, publicly funded grocery stores and a state-run bank.
The stances seem to have paid off as Hong has gained momentum in recent months, and, with under two weeks to go until the primary, looks poised to capture the Democratic nomination.
‘FREE BEER’ FOR TRUMP DEATH DEM ACTIVIST RUNNING FOR WISCONSIN GOV: ‘I WILL WIN’ IF THEY SILENCE ME
Wisconsin gubernatorial candidate Francesca Hong. (Matthew Ludak for The Washington Post via Getty Images)
Hong also started getting mocked Friday for a resurfaced 2019 post where she said, «I ate two bites of my kid’s cheeseburger at a Culver’s in black river falls and told him they ran out of ice cream. Mostly just wanted to leave bc I was on the verge of a anxiety attack…to (sic) many old white people who didn’t think we spoke english.»
«Omg English ***TOO **AN,» she replied.
«Bold choice for Democrats in Wisconsin running someone statewide who gets a panic attack at Culver’s at the sight of ‘old white people,’» Former White House Principal Deputy Communications Director Alex Pfeiffer wrote on X.
«The only way this post could be worse for someone running for office in Wisconsin is if she had complained that Culver’s uses too much butter,» Chuck Ross, an investigative reporter at the Washington Free Beacon, wrote on X.
«One of the democrats running for Governor of Wisconsin doesn’t know that Culver’s serves only fresh frozen custard. She thinks they serve ice cream. Disqualifying,» Brick Suit, an online MAGA personality, wrote on X.
The race was shaken up on Thursday when Mandela Barnes, the state’s former lieutenant governor, dropped out of the race. Barnes was considered a frontrunner in the race because of his proximity to outgoing Gov. Tony Evers and his name recognition.
His exit also coincides with rumblings that Barnes may have abused his position in the past to make sexual advances toward women in the workplace, an allegation currently under investigation by The Milwaukee Journal Sentinel.
With his departure, Hong and Milwaukee County Executive David Crowley were left as the two main contenders.
Hong has received backing from a number of nationally recognized progressives, including Rep. Ilhan Omar, D-Minn., and Rep. Ro Khanna, D-Calif. She has raised nearly $709,000 as of late June, according to state records.
SCHIFF-BACKED CANDIDATE ABRUPTLY ENDS GUBERNATORIAL CAMPAIGN AMID RUMBLINGS OF A DAMAGING REPORT
Wisconsin state Rep. Francesca Hong, a Democratic Socialist candidate for governor, poses for a portrait at St. Paul Baptist Church on July 19, 2026, in Racine, Wis. (Sara Stathas/For The Washington Post via Getty Images)
By comparison, Crowley has secured $250,000 and enjoys the support of a number of local organizations and figures.
Gov. Evers has endorsed Crowley , citing his experience.The gubernatorial primary will take place Aug. 11.
Fox News Digital has reached out to Hong’s campaign for comment.
wisconsin, gubernatorial, politics
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