Tech News
Jupiter's Great Red Spot Is Shapeshifting in Ways 'Never Identified Before'
science - Posted On:2024-10-10 13:30:00 Source: slashdot
An anonymous reader writes: A massive storm has been raging on Jupiter for centuries, and, for the most part, has appeared very serious. A new series of detailed images, however, revealed that the famous red cyclone can get a little squiggly, bulging into different shapes and sizes over a short period of time. Astronomers used the Hubble space telescope to look at Jupiter's Great Red Spot (GRS) from December 2023 to March 2024, and they observed the massive storm changing dimensions over the 90-day period. The reason behind this unexpected shapeshifting is unknown, but it revealed that the famous red storm is not as stable as it seemed. The results of the Hubble observations are detailed in a study published Wednesday in The Planetary Science Journal. Using Hubble's observations, the team of astronomers behind the new study measured the Great Red Spot's size, shape, brightness, color, and vorticity over one full oscillation cycle. The combined images act like a time-lapse of the storm's changing behavior, revealing its famous red eye varying in size, while its core gets brighter when the Great Red Spot is at its largest during the 90-day cycle. Read more of this story at Slashdot.
Rises In Life Expectancy Have Slowed Dramatically, Analysis Finds
science - Posted On:2024-10-10 03:15:00 Source: slashdot
The rapid increases in life expectancy seen in the 20th century have slowed significantly, according to a new analysis published in the journal Nature. The Guardian reports: According to the study, children born recently in regions with the oldest people are far from likely to become centenarians. At best, the researchers predict 15% of females and 5% of males in the oldest-living areas will reach 100 this century. "If you're planning for retirement, it's probably not a good idea to assume you're going to make it to 100," said Jay Olshansky, professor of epidemiology and biostatistics at the University of Illinois at Chicago. "You'd probably have to work for at least 10 years longer than you'd think. And you want to enjoy the last phase of your life, you don't necessarily want to spend it working to save for time you're not going to experience." Advances in public health and medicine sparked a longevity revolution in the 20th century. In the previous 2,000 years, life expectancy crept up, on average, one year every century or two. In the 20th century, average life expectancy rocketed, with people gaining an extra three years every decade. For the latest study, Olshansky delved into national statistics from the US and nine regions with the highest life expectancies, focusing on 1990 to 2019, before the Covid pandemic struck. The data from Hong Kong, Japan, South Korea, Australia, France, Italy, Switzerland, Sweden, and Spain showed that rises in life expectancy had slowed dramatically. In the US, life expectancy fell [T]he researchers describe how on average, life expectancy in the longest-living regions rose only 6.5 years between 1990 and 2019. They predict that girls born recently in the regions have only a 5.3% chance of reaching 100 years old, while boys have a 1.8% chance. "In the modern era we have, through public health and medicine, manufactured decades of life that otherwise would not exist," Olshansky said. "These gains must slow down. The longevity game we're playing today is different to the longevity game we played a century ago when we were saving infants and children and women of child-bearing age and the gains in life expectancy were large. Now the gains are small because we're saving people in their 60s, 70s, 80s, and 90s." Olshansky said it would take radical new treatments that slow ageing, the greatest risk factor for many diseases, to achieve another longevity revolution. Research in the field is afoot with a dozen or so drugs shown to increase the lifespan of mice. Read more of this story at Slashdot.
Rapid analysis finds climate change’s fingerprint on Hurricane Helene
Science - Posted On:2024-10-09 18:45:00 Source: arstechnica
Hurricane Helene crossed the Gulf of Mexico at a time when sea surface temperatures were at record highs and then barreled into a region where heavy rains had left the ground saturated. The result was historic catastrophic flooding.
One key question is how soon we might expect history to repeat itself. Our rapidly warming planet has tilted the odds in favor of some extreme weather events in a way that means we can expect some events that had been extremely rare to start occurring with some regularity. Our first stab at understanding climate change's influence on Helene was released on Wednesday, and it suggests that rainfall of the sort experienced by the Carolinas may now be a once-in-70-year event, which could have implications for how we rebuild some of the communities shattered by the rain.
The quick analysis was done by the World Weather Attribution project, which has developed peer-reviewed methods of looking for the fingerprints of climate change in major weather events. In general, this involves identifying the key weather patterns that produced the event and then exploring their frequency using climate models run with and without the carbon dioxide we've added to the atmosphere.
Eating Less Can Lead To a Longer Life: Massive Study in Mice Shows Why
science - Posted On:2024-10-09 15:45:00 Source: slashdot
Cutting calorie intake can lead to a leaner body -- and a longer life, an effect often chalked up to the weight loss and metabolic changes caused by consuming less food. Now, one of the biggest studies of dietary restrictions ever conducted in laboratory animals challenges the conventional wisdom about how dietary restriction boosts longevity. From a report: The study, involving nearly 1,000 mice fed low-calorie diets or subjected to regular bouts of fasting, found that such regimens do indeed cause weight loss and related metabolic changes. But other factors -- including immune health, genetics and physiological indicators of resiliency -- seem to better explain the link between cutting calories and increased lifespan. "The metabolic changes are important," says Gary Churchill, a mouse geneticist at the Jackson Laboratory in Bar Harbor, Maine, who co-led the study. "But they don't lead to lifespan extension." To outside investigators, the results drive home the intricate and individualized nature of the body's reaction to caloric restriction. "It's revelatory about the complexity of this intervention," says James Nelson, a biogerontologist at the University of Texas Health Science Center in San Antonio. The study was published today in Nature by Churchill and his co-authors, including scientists at Calico Life Sciences in South San Francisco, California, the anti-ageing focused biotech company that funded the study. Scientists have long known that caloric restriction, a regimen of long-term limits on food intake, lengthens lifespan in laboratory animals. Some studies have shown that intermittent fasting, which involves short bouts of food deprivation, can also increase longevity. Read more of this story at Slashdot.
Google identifies low noise “phase transition” in its quantum processor
Science - Posted On:2024-10-09 15:30:00 Source: arstechnica
Back in 2019, Google made waves by claiming it had achieved what has been called "quantum supremacy"—the ability of a quantum computer to perform operations that would take a wildly impractical amount of time to simulate on standard computing hardware. That claim proved to be controversial, in that the operations were little more than a benchmark that involved getting the quantum computer to behave like a quantum computer; separately, improved ideas about how to perform the simulation on a supercomputer cut the time required down significantly.
But Google is back with a new exploration of the benchmark, described in a paper published in Nature on Wednesday. It uses the benchmark to identify what it calls a phase transition in the performance of its quantum processor and uses it to identify conditions where the processor can operate with low noise. Taking advantage of that, they again show that, even giving classical hardware every potential advantage, it would take a supercomputer a dozen years to simulate things.
The benchmark in question involves the performance of what are called quantum random circuits, which involves performing a set of operations on qubits and letting the state of the system evolve over time, so that the output depends heavily on the stochastic nature of measurement outcomes in quantum mechanics. Each qubit will have a probability of producing one of two results, but unless that probability is one, there's no way of knowing which of the results you'll actually get. As a result, the output of the operations will be a string of truly random bits.
Octopus suckers inspire new tech for gripping objects underwater
Science - Posted On:2024-10-09 15:30:00 Source: arstechnica
Over the last few years, Virginia Tech scientists have been looking to the octopus for inspiration to design technologies that can better grip a wide variety of objects in underwater environments. Their latest breakthrough is a special switchable adhesive modeled after the shape of the animal's suckers, according to a new paper published in the journal Advanced Science.
“I am fascinated with how an octopus in one moment can hold something strongly, then release it instantly. It does this underwater, on objects that are rough, curved, and irregular—that is quite a feat,” said co-author and research group leader Michael Bartlett. "We’re now closer than ever to replicating the incredible ability of an octopus to grip and manipulate objects with precision, opening up new possibilities for exploration and manipulation of wet or underwater environments.”
As previously reported, there are several examples in nature of efficient ways to latch onto objects in underwater environments, per the authors. Mussels, for instance, secrete adhesive proteins to attach themselves to wet surfaces, while frogs have uniquely structured toe pads that create capillary and hydrodynamic forces for adhesion. But cephalopods like the octopus have an added advantage: The adhesion supplied by their grippers can be quickly and easily reversed, so the creatures can adapt to changing conditions, attaching to wet and dry surfaces.
Protein structure and design software gets the Chemistry Nobel
Science - Posted On:2024-10-09 11:45:00 Source: arstechnica
On Wednesday, the Nobel Committee announced that it had awarded the Nobel Prize in chemistry to researchers who pioneered major breakthroughs in computational chemistry. These include two researchers at Google's DeepMind in acknowledgment of their role in developing AI software that could take a raw protein sequence and use it to predict the three-dimensional structure the protein would adopt in cells. Separately, the University of Washington's David Baker was honored for developing software that could design entirely new proteins with specific structures.
The award makes for a bit of a theme for this year, as yesterday's Physics prize honored AI developments. In that case, the connection to physics seemed a bit tenuous, but here, there should be little question that the developments solved major problems in biochemistry.
DeepMind, represented by Demis Hassabis and John Jumper, had developed AIs that managed to master games as diverse as chess and StarCraft. But it was always working on more significant problems in parallel, and in 2020, it surprised many people by announcing that it had tackled one of the biggest computational challenges in existence: the prediction of protein structures.
NOAA drops scientist’s ashes into the eye of Category 5 Milton
Science - Posted On:2024-10-09 11:45:00 Source: arstechnica
On Tuesday evening during a measurement flight, the NOAA Aircraft Operations Center dropped the ashes of Peter Dodge, a longtime radar scientist and hurricane hunter, in the eye of Hurricane Milton. The drop honored Dodge's 44-year career and his contributions to radar meteorology and tropical cyclone research.
As the powerful and dangerous storm bears down on Florida, the release of Dodge's ashes was an unusually peaceful moment during a type of flight that is typically quite turbulent. Michael Lowry, a Hurricane Specialist and Storm Surge Expert at WPLG-TV in Florida, celebrated the moment on X, calling it a "beautiful tribute."
Lowry's post included a screenshot of a Vortex Data Message, which is a log of in-flight observations made by hurricane reconnaissance aircraft, detailing the storm's center location, pressure, wind speed, temperature, and other key meteorological data used to assess the intensity and structure of the cyclone. At the end, a tribute line reads, "PETER DODGE HX SCI (1950–2023) 387TH PENNY."
Google DeepMind Scientists Win Nobel Chemistry Prize for Work on Proteins
science - Posted On:2024-10-09 10:15:01 Source: slashdot
Three scientists won the 2024 Nobel Prize in Chemistry on Wednesday for their groundbreaking work in predicting and designing protein structures, the Royal Swedish Academy of Sciences announced in Stockholm. David Baker of the University of Washington shares the prize with Demis Hassabis and John Jumper of Google DeepMind. Baker pioneered the creation of novel proteins, while Hassabis and Jumper developed AlphaFold, an AI model that predicts protein structures from amino acid sequences. The laureates will split the 11 million Swedish kronor ($1 million) award for their contributions to computational protein design and structure prediction. Baker's team has produced proteins with applications in medicine and materials science since his initial breakthrough in 2003. Hassabis and Jumper's AlphaFold, announced in 2020, has predicted structures for nearly all 200 million known proteins. "We glimpsed at the beginning that it might be possible to create a whole new world of proteins that address a lot of the problems faced by humans in the 21st century," Baker said at a press briefing. "Now it's becoming possible," Heiner Linke, chair of the Nobel chemistry committee, called the discoveries "spectacular," noting they fulfilled a 50-year-old dream of predicting protein structures from amino acid sequences. The breakthroughs have wide-ranging implications, from understanding antibiotic resistance to developing enzymes that decompose plastic. Over 2 million researchers worldwide have already utilized AlphaFold in various applications. Read more of this story at Slashdot.
Researchers Claim New Technique Slashes AI Energy Use By 95%
science - Posted On:2024-10-08 23:45:00 Source: slashdot
Researchers at BitEnergy AI, Inc. have developed Linear-Complexity Multiplication (L-Mul), a technique that reduces AI model power consumption by up to 95% by replacing energy-intensive floating-point multiplications with simpler integer additions. This method promises significant energy savings without compromising accuracy, but it requires specialized hardware to fully realize its benefits. Decrypt reports: L-Mul tackles the AI energy problem head-on by reimagining how AI models handle calculations. Instead of complex floating-point multiplications, L-Mul approximates these operations using integer additions. So, for example, instead of multiplying 123.45 by 67.89, L-Mul breaks it down into smaller, easier steps using addition. This makes the calculations faster and uses less energy, while still maintaining accuracy. The results seem promising. "Applying the L-Mul operation in tensor processing hardware can potentially reduce 95% energy cost by element wise floating point tensor multiplications and 80% energy cost of dot products," the researchers claim. Without getting overly complicated, what that means is simply this: If a model used this technique, it would require 95% less energy to think, and 80% less energy to come up with new ideas, according to this research. The algorithm's impact extends beyond energy savings. L-Mul outperforms current 8-bit standards in some cases, achieving higher precision while using significantly less bit-level computation. Tests across natural language processing, vision tasks, and symbolic reasoning showed an average performance drop of just 0.07% -- a negligible tradeoff for the potential energy savings. Transformer-based models, the backbone of large language models like GPT, could benefit greatly from L-Mul. The algorithm seamlessly integrates into the attention mechanism, a computationally intensive part of these models. Tests on popular models such as Llama, Mistral, and Gemma even revealed some accuracy gain on certain vision tasks. At an operational level, L-Mul's advantages become even clearer. The research shows that multiplying two float8 numbers (the way AI models would operate today) requires 325 operations, while L-Mul uses only 157 -- less than half. "To summarize the error and complexity analysis, L-Mul is both more efficient and more accurate than fp8 multiplication," the study concludes. But nothing is perfect and this technique has a major achilles heel: It requires a special type of hardware, so the current hardware isn't optimized to take full advantage of it. Plans for specialized hardware that natively supports L-Mul calculations may be already in motion. "To unlock the full potential of our proposed method, we will implement the L-Mul and L-Matmul kernel algorithms on hardware level and develop programming APIs for high-level model design," the researchers say. Read more of this story at Slashdot.
SpaceX’s next Starship launch—and first catch—could happen this weekend
Science - Posted On:2024-10-08 17:45:00 Source: arstechnica
We may not have to wait as long as we thought for the next test flight of SpaceX's Starship rocket.
The world's most powerful launcher could fly again as soon as Sunday, SpaceX says, assuming the Federal Aviation Administration grants approval. The last public statement released from the FAA suggested the agency didn't expect to determine whether to approve a commercial launch license for SpaceX's next Starship test flight before late November.
There's some optimism at SpaceX that the FAA might issue a launch license much sooner, perhaps in time for Starship to fly this weekend. The launch window Sunday opens at 7 am CDT (8 am EDT; 12:00 UTC), about a half-hour before sunrise at SpaceX's Starbase launch site in South Texas.
Injured comb jellies can fuse into a single organism
Science - Posted On:2024-10-08 14:15:00 Source: arstechnica
Comb jellies, technically known as ctenophores, are one of the weirdest creatures on Earth. They appeared in the seas over half a billion years ago and have maintained to the present day the comb-like rows of cilia they used to move around. Their transparent bodies and internal bioluminescence give them looks that rival gaming computers. But there’s something that makes them even weirder.
When a comb jelly is injured, it can regenerate at an amazing rate. But it can also attach a body part of another injured comb jelly and integrate it near-seamlessly into its own body. (Those who have played Elden Ring can enjoy comparisons to Godrick The Grafted.)
“I’ve been observing ctenophores for a long time, so it was easy to spot an unusually large specimen. Some of the anatomical features were doubled, so I realized what I’m looking at is actually two individuals that have fused together,” said Kei Jokura, a marine researcher at the University of Exeter and lead author of a recent Current Biology paper on the integration of fused ctenophores.
The Problems With Polls
science - Posted On:2024-10-08 10:45:00 Source: slashdot
Political polling, once hailed as a revolutionary tool for democracy, is facing a crisis of confidence amid high-profile failures and fundamental critiques. Data scientist G. Elliott Morris, Nate Silver's successor at FiveThirtyEight, has defended polling's relevance in a new book, arguing it remains crucial for revealing public opinion despite challenges like plummeting response rates and rising costs. But critics, including political scientist Lindsay Rogers and sociologist Leo Bogart, have long questioned polling's ability to capture the complexities of public sentiment, arguing it reduces nuanced political matters to simplistic yes/no questions and potentially records opinions that don't exist outside the survey context. Social media platforms, promising to transform democracy by facilitating constant public feedback, have further complicated the polling landscape. The story adds: Today that product remains overwhelmingly popular: polls saturate election coverage, turn politics into a spectator sport, and provide an illusion of control over complex, unpredictable, and fundamentally fickle social forces. That isn't to say that polls don't have uses beyond entertainment: they can be a great asset to campaigns, helping candidates refine their messages and target their resources; they can provide breakdowns of election results that are far more illuminating than the overall vote count; and they can give us a sense -- a vague and sometimes misleading sense -- of what 300 million people or more think about an issue. But, pace Morris, the time for celebrating polls as a bastion of democracy or as a means of bringing elites closer to voters is surely over. The polling industry continues to boom. Democracy isn't faring quite so well. Silicon Valley ultimately peddled the same feel-good story about democracy as the polling industry: that the powerful are unresponsive to the wider public because they cannot hear their voices, and if only they could hear them, then of course they would listen and act. The virtue of this diagnosis is that structural inequalities in wealth and power are left intact -- all that matters in democracy is that everyone has a voice, regardless of background. In a very narrow, technical sense, their innovations have made this a reality. But the result is a loud, opinionated, and impotent public sphere, coarsened by social and economic divisions and made all the more disillusioned by the discovery that, in politics, it takes more than a voice to be heard. Read more of this story at Slashdot.
Archaeologists found an ancient Egyptian observatory
Science - Posted On:2024-10-08 08:30:01 Source: arstechnica
A few years ago, Egyptian archaeologists discovered what they thought were the ruins of an ancient Egyptian temple dating back to the sixth century BCE. Subsequent finds at the site indicate that the structure was actually an astronomical observatory, deemed the first and largest such structure yet found, according to Egypt's Ministry of Tourism and Antiquities.
The L-shaped structure was found within a larger complex called the Temple of Buto (a later Greek name), known to the ancient Egyptians as Per-Wadjet and located east of Alexandria in the Nile Delta. It's now called Tell El Fara'in ("Hill of the Pharaohs"). Buto was once a sacred site dedicated to the goddess Wadjet, believed to be the matron and protector of lower Egypt, who took on a cobra form. Buto was well-known for its temple and the oracle of Wadjet, with an annual festival held there in her honor.
There were archaeological excavations of the site in the 1960s and 1980s, revealing a palace dating back to the Second Dynasty, as well as six Greek bathhouses. An Egyptian team began fresh excavations a few years ago. In 2022, they uncovered a hall at the southwestern end of the temple, with the remains of three papyrus-shaped columns aligned on a north-south axis. They also found engraved stone fragments and a limestone painting of a bird's head wearing a white crown within two feathers.
Nobel Prize in Physics Goes To Machine Learning Pioneers Hopfield and Hinton
science - Posted On:2024-10-08 07:45:00 Source: slashdot
John J. Hopfield of Princeton University and Geoffrey E. Hinton of the University of Toronto were awarded the Nobel Prize in Physics on Tuesday for their groundbreaking work in machine learning. The Royal Swedish Academy of Sciences recognized the scientists for developing artificial neural networks capable of recognizing patterns in large data sets, laying the foundation for modern AI applications like facial recognition and language translation. Hopfield, 91, created an associative memory system for storing and reconstructing data patterns. Hinton, 76, invented a method for autonomous data property identification. "This year's physics laureates' breakthroughs stand on the foundations of physical science," the Nobel Committee stated. "They have shown a completely new way for us to use computers to tackle many of society's challenges." The laureates will share the 11 million Swedish kronor ($1.1 million) prize. Read more of this story at Slashdot.
Spacecraft Launches Toward Asteroid Knocked Off Course By NASA
science - Posted On:2024-10-08 03:15:01 Source: slashdot
The Hera spacecraft, launched by the European Space Agency on Monday, is on a mission to study the aftermath of NASA's 2022 test that successfully knocked the Dimorphos asteroid off course by intentionally crashing a probe into it. It's scheduled to arrive in December 2026. The BBC reports: The Hera craft launched from Cape Canaveral in Florida at 10:52 local time (15:52BST) on Monday. [...] The Hera mission, which is run by the European Space Agency, is a follow-on from Nasa's Double Asteroid Redirection Test (DART) project. Dimorphos is a small moon 160m-wide that orbits an asteroid close to Earth called Didymos in something called a binary asteroid system. In 2022 Nasa said it successfully changed Dimorphos's course by crashing a probe into it. It altered the rock's path by a few meters, according to Nasa's scientists. The asteroid was not on course to hit Earth, but it was a test to see whether space agencies could do it when there is genuine risk. When it arrives in two years, the Hera craft will look at the size and depth of the impact crater created on Dimorphos. Two cube-shaped probes will also study the make-up of the asteroid and its mass. Read more of this story at Slashdot.
SpaceX launches Europe’s Hera asteroid mission ahead of Hurricane Milton
Science - Posted On:2024-10-07 18:15:00 Source: arstechnica
Two years ago, a NASA spacecraft smashed into a small asteroid millions of miles from Earth to test a technique that could one day prove useful to deflect an object off a collision course with Earth. The European Space Agency launched a follow-up mission Monday to go back to the crash site and see the damage done.
The nearly $400 million (363 million euro) Hera mission, named for the Greek goddess of marriage, will investigate the aftermath of a cosmic collision between NASA's DART spacecraft and the skyscraper-size asteroid Dimorphos on September 26, 2022. NASA's Double Asteroid Redirection Test mission was the first planetary defense experiment, and it worked, successfully nudging Dimorphos off its regular orbit around a larger companion asteroid named Didymos.
But NASA had to sacrifice the DART spacecraft in the deflection experiment. Its destruction meant there were no detailed images of the condition of the target asteroid after the impact. A small Italian CubeSat deployed by DART as it approached Dimorphos captured fuzzy long-range views of the collision, but Hera will perform a comprehensive survey when it arrives in late 2026.
MicroRNA Pioneers Win Nobel Prize in Medicine
science - Posted On:2024-10-07 17:00:00 Source: slashdot
American scientists Victor Ambros and Gary Ruvkun won the Nobel Prize in Physiology or Medicine on Monday for discovering microRNA, tiny molecules that regulate gene expression. Their groundbreaking work in the 1990s revealed a new layer of genetic control, opening fresh avenues for understanding human development and disease. Ambros first identified microRNA in 1993, while Ruvkun later found similar molecules in humans and other species. These RNA fragments, about 100 times smaller than typical messenger RNA, can silence genes and fine-tune protein production. The discovery has spurred research into potential treatments for cancer, heart disease, and neurological disorders. Several biotechnology companies are now developing drugs that target or mimic microRNAs. Read more of this story at Slashdot.
Hurricane Milton becomes second-fastest storm to reach Category 5 status
Science - Posted On:2024-10-07 13:45:00 Source: arstechnica
In less than a day, Hurricane Milton has rapidly intensified over the southern Gulf of Mexico, exploding from a small Category 1 hurricane into a Category 5 storm. Unfortunately, the hurricane is likely to strengthen further as it tracks eastward toward Florida.
The National Hurricane Center reported that Milton had reached sustained winds of 160 mph as of 11:44 pm ET on Monday, with a central pressure of 925 millibars. The storm is moving steadily eastward and is likely to reach the west coast of Florida on Wednesday evening as a major hurricane.
Based upon Atlantic basin records, Milton has tied Hurricane Maria (2017) for the second-fastest intensification from a Category 1 to Category 5 hurricane, taking just 18 hours. Only Hurricane Wilma (2005) did so more rapidly, in just 12 hours.
Medicine Nobel goes to previously unknown way of controlling genes
Science - Posted On:2024-10-07 13:45:00 Source: arstechnica
On Monday, the Nobel Committee announced that two US researchers, Victor Ambros and Gary Ruvkun, will receive the prize in Physiology or Medicine for their discovery of a previously unknown mechanism for controlling the activity of genes. They discovered the first of what is now known to be a large collection of MicroRNAs, short (21-23 bases long) RNAs that bind to and alter the behavior of protein-coding RNAs. While first discovered in a roundworm, they've since been discovered to play key roles in the development of most complex life.
The story behind the discovery is typical of a lot of the progress in the biological sciences: genetics helps identify a gene important for the development of one species, and then evolutionary conservation reveals its widespread significance.
Ambros and Ruvkun started on the path to discovery while post-doctoral fellows in the lab of earlier Nobel winner Robert Horvitz, who won for his role in developing the roundworm C. elegans as an experimental genetic organism. As part of the early genetic screens, people had identified a variety of mutations that caused developmental problems for specific lineages of cells. These lin mutations included lin-4, which Ambros was characterizing. It lacked a number of specialized cell types, as well as the physical structures that depended on them.