Tech

Scientists reveal origin of mammal evolution milestone: warm-bloodedness

Published

2 years ago

Farwa

Researchers study reduced size of inner ear in fossils of mammal forerunners.
Endothermy is defining feature of mammals including humans.
Mammalian lineage evolved from cold-blooded creatures.

WASHINGTON: Scientists have answered a longstanding question about mammalian evolution, examining ear anatomy of living and extinct mammals and their close relatives to determine when warm-bloodedness — a trait integral to the lineage’s success — first emerged.

Researchers said on Wednesday that the reduced size of inner ear structures called semicircular canals — small, fluid-filled tubes that help in keeping balance — in fossils of mammal forerunners showed that warm-bloodedness, called endothermy, arose roughly 233 million years ago during the Triassic Period.

These first creatures that attained this milestone, called mammaliamorph synapsids, are not formally classified as mammals, as the first true mammals appeared roughly 30 million years later. But they had begun to acquire traits associated with mammals.

Endothermy evolved at a time when important features of the mammal body plan were falling into place, including whiskers and fur, changes to the backbone related to gait, the presence of a diaphragm, and a more mammal-like jaw joint and hearing system.

“Endothermy is a defining feature of mammals, including us humans. Having a quasi-constant high body temperature regulates all our actions and behaviours, from food intake to cognition, from locomotion to the places where we live,” said palaeontologist Ricardo Araújo of the University of Lisbon’s Institute of Plasmas and Nuclear Fusion, co-lead author of the study published in the journal Nature.

The high metabolisms of mammal bodies maintain internal temperature independent of their surroundings. Cold-blooded animals like lizards adopt strategies like basking in the sun to warm up.

Mammalian endothermy arrived at an eventful evolutionary moment, with dinosaurs and flying reptiles called pterosaurs — creatures that long would dominate ecosystems — first appearing at about that time. Endothermy offered advantages.

“Run faster, run longer, be more active, be active through longer periods of the circadian cycle, be active through longer periods of the year, increase foraging area. The possibilities are endless. All this at a great cost, though. More energy requires more food, more foraging, and so on. It is a fine balance between the energy you spend and the energy you intake,” Araújo said.

The mammalian lineage evolved from cold-blooded creatures, some boasting exotic body plans like the sail-backed Dimetrodon, mixing reptile-like traits like splayed legs and mammal-like traits like the arrangement of certain jaw muscles.

Endothermy emerged relatively quickly, in perhaps less than a million years, rather than a longer, gradual process, said paleontologist and study co-lead author Romain David of the Natural History Museum in London.

An early example was a vaguely weasel-like species, Pseudotherium argentinus, in Argentina about 231 million years ago. The later true mammals were the ancestors of today’s three mammalian groups: placentals, marsupials and monotremes.

“Given how central endothermy is to so many aspects of the body plan, physiology and lifestyle of modern mammals, when it evolved in our ancient ancestors has been a really important unsolved question in paleontology,” said paleontologist and study co-author Ken Angielczyk of the Field Museum in Chicago.

Determining when endothermy originated through fossils has been tough. As Araújo noted: “We cannot stick thermometers in the armpit of your pet Dimetrodon, right?”

The inner ear provided a solution. The viscosity, or runniness, of inner ear fluid — and all fluid — changes with temperature. This fluid in cold-blooded animals is cooler and thicker, necessitating wider canals. Warm-blooded animals have less viscous ear fluid and smaller semicircular canals.

The researchers compared semicircular canals in 341 animals, 243 extant and 64 extinct. This showed endothermy arriving millions of years later than some prior estimates.

Mammals played secondary roles in ecosystems dominated by dinosaurs before taking over after the mass extinction event 66 million years ago. Among today’s animals, mammals and birds are warm-blooded.

“It is maybe too far-fetched, but interesting, to think that the onset of endothermy in our ancestors may have ultimately led to the construction of the Giza pyramids or the development of the smartphone,” Araújo said. “If our ancestors would have not become independent of environmental temperatures, these human achievements would probably not be possible.”

Latest News

Bitcoin makes its first breach of $94,000.

Published

2 days ago

Farwa

As news broke that Donald Trump’s social media company was in negotiations to acquire cryptocurrency trading platform Bakkt (BKKT.N), Bitcoin surged to a record high above $94,000, adding to optimism that the next Trump administration would be cryptocurrency-friendly.

This year, Bitcoin, the largest and most well-known cryptocurrency in the world, has more than doubled in value. Just before the close of the previous session, it reached a record high of $94,078 before closing at $92,104 in Asian hours on Wednesday.

According to the Financial Times, which cited two persons with knowledge, NYSE-owner Intercontinental Exchange (ICE.N) is supporting Trump Media and Technology Group (DJT.O), opens new tab, which runs Truth Social, in its pursuit of an all-stock purchase of Bakkt.

In addition to traders taking advantage of the first day of options trading on the Nasdaq over BlackRock’s Bitcoin ETF (IBIT.O), Tony Sycamore, market analyst at IG, stated that the Trump deal chatter had helped push bitcoin to a record high.

As traders hoped that President-elect Trump’s pledged support for digital assets would result in a less stringent regulatory framework and give bitcoin a boost after a sluggish few months, cryptocurrencies have surged since the U.S. election on November 5.

According to data and analytics aggregator CoinGecko, the global cryptocurrency market is now worth over $3 trillion, a new high, due to the growing excitement.

Australian online broker Pepperstone’s head of research, Chris Weston, stated that there is genuine underlying purchasing pressure on bitcoin and that “another kick higher should bring in a fresh chase from those who like to buy what’s strong.”

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The PTA discloses how many VPNs are registered in Pakistan.

Published

3 days ago

Farwa

Speaking at the Senate Standing Committee on IT meeting in Islamabad, which was presided over by Palwasha Khan, was the PTA chief.

The continuous regulation of Virtual Private Networks (VPNs) in Pakistan was the main topic of discussion. The committee called for the next meeting and voiced concerns about the Minister of State for IT’s absence for the third consecutive session.

“We have spent the last two years developing VPN legislation. Uninterrupted internet connection is guaranteed by registered VPNs without sacrificing privacy, according to the PTA chairman.

During the session, Senator Muhammad Humayun criticized the measures, saying, “Shutting down platforms like X (formerly Twitter) is jeopardizing the entire IT industry and impacting the livelihoods of over 2.5 million individuals in Pakistan.”

He opposed laws that would hurt independent contractors and small companies.

Although the PTA promised that registered VPNs would not experience internet outages, committee members wanted to know the exact legal foundation for these regulations. Senator Kamran Murtaza asked for documents that detailed the requirements for registration.

“If VPN services are abruptly halted, there will be a major backlash,” Senator Afnan Ullah said. While pointing out that Pakistan’s IT exports had increased by 20% in the previous year, he emphasised that the sector was still lagging behind India.

Concerns over the viability of the existing VPN whitelist method were voiced by the committee. While IT officials admitted that more than 1 million freelancers in Pakistan rely significantly on VPNs for their business, Senator Humayun pointed out that the laws should be more beneficial than harmful.

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Pakistan declares AI chatbots to be dangers to security.

Published

1 week ago

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The National Computer Emergency Response Team (CERT) has released a security advisory concerning the increasing utilization of artificial intelligence (AI) chatbots, emphasizing potential hazards related to the exposing of private data.

The recommendation recognizes that AI chatbots, like ChatGPT, have gained significant popularity for personal and professional duties owing to their capacity to improve productivity and engagement. Nonetheless, the CERT cautions that these AI systems frequently retain sensitive information, so posing a danger of data breaches.

Engagements with AI chatbots may encompass sensitive information, such as corporate strategy, personal dialogues, or confidential correspondence, which could be compromised if inadequately safeguarded. The warning emphasizes the necessity for a comprehensive cybersecurity framework to alleviate concerns associated with AI chatbot utilization.

Users are advised against inputting critical information into AI chatbots and are encouraged to deactivate any chat-saving functionalities to mitigate the danger of unwanted data access. The CERT additionally advises performing routine system security checks and employing monitoring tools to identify any anomalous behavior from AI chatbots.

Organizations are urged to adopt rigorous security protocols to safeguard against possible data breaches resulting from AI-driven interactions.