Category Archives: Evolution

More Americans are coming to accept Charles Darwin's "dangerous idea" of evolution, according to thirty years' worth of national surveys.

Researchers have found that public acceptance of biological evolution has increased substantially in the last decade alone, following twenty years of relative stagnancy.

Between 1985 and 2010, roughly 40 percent of surveyed adults in the US agreed that "human beings, as we know them today, developed from earlier species of animals". Taking into account the small number of fence-sitters, this suggests much of the nation was evenly divided on the theory.

By 2016, that percentage had, at last, become a majority, reaching 54 percent.

As it turns out, education has played a crucial role in that shift. When researchers began to analyze the demographics of survey respondents over the past thirty years, they noticed the completion of one or more college science courses was the strongest predictor of evolution acceptance.

"Almost twice as many Americans held a college degree in 2018 as in 1988," says Mark Ackerman, who studies collective intelligence at the University of Michigan.

"It's hard to earn a college degree without acquiring at least a little respect for the success of science."

In the current analysis, the proportion of American adults with scientific literacy increased from 11 percent in 1988 to 31 percent in 2019.

That rise in knowledge can also easily spread to others. For instance, research suggests fewer students are exposed to creationism in the science classroom due in part to new teachers replacing a generation of educators less suited to teaching evolution.

Still, even a healthy dose of education can only go so far. Some researchers, for instance,think religious beliefs are a stronger predictor of accepting evolution than educational attainment.But this is an area of research that is still hotly debated. It could be, for instance, that education only works for some individuals who don't interpret the Bible literally.

In the US, evolution has become a highly politicized topic, especially among supporters of the Republican party, which tends to align its policies with evangelical Christian values.

The result is that today, the US has some of the lowest acceptance rates for evolution in the developed world, with only Turkey scoring lower.

Even now that a majority of Americans do not reject evolution, the rate of acceptance is still low compared to other nations and much lower than scientific consensus.

In recent years, religious adherence has begun to decline in the US, but the political divide on evolution still very much exists.

In 2019, researchers found 83 percent of liberal Democrats accepted evolution, whereas only 34 percent of conservative Republicans felt the same.

The driving force behind this huge difference is probably not ideological partisanship, experts say, but fundamental religious beliefs, which Republicans tend to hold more.

For instance, roughly 30 percent of American adults hold fundamental religious beliefs that directly contradict evolutionary theory, which is almost the same percentage of conservative Republicans that rejected evolution in the current analysis.

The authors of the current study are not ruling out religion as an influential factor. Their analysis still shows that fundamental religious beliefs can change the acceptance of evolution among American adults. But at least according to their analysis, it seems that educational attainment is the more influential factor.

According to their analysis, the recent increase in acceptance mostly comes from American adults who were previously unsure about the theory. Only some who outright rejected evolution had their mind's changed over time.

"Although scientific literacy has grown, and science continues to have pervasive influence in American society," the authorswrite, "a tension between religious fundamentalism and evolution remains."

While religion clearly remains a barrier to further public acceptance of evolution, that's gradually beginning to change. In 1988, the current analysis found only 8 percent of religious fundamentalists accepted the theory of evolution. Whereas in 2019, nearly a third did.

Along with growing exposure to scientific courses, a decline in religious fundamental beliefs will no doubt see the minority of Americans that reject evolution continue to shrink.

Last year, Pew conducted a more global surveythat showed a slightly higher acceptance of evolution in the US at around 64 percent.

It's a number that nonetheless falls far below nations such as Canada (77 percent), Germany (81 percent), and Japan (88 percent), showing the US still has some catching up to do.

The study was published in Public Understanding of Science.

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More Americans Are Finally Coming Around to Accepting The Science of Evolution - ScienceAlert

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Tiny tardigrades walk in a manner most closely resembling that of insects 500,000 times their size, according to new research.

Tardigrades earned the nickname water bears when scientists first observed the 0.02-inch-long animals distinctive gaits in the 18th century. Their dumpy plod raises the question of why they evolved to walk at all.

Animals as small and soft as tardigrades seldom have legs and almost never bother walking. For example, round worms of similar size and body type thrash about, slithering their doughy forms over unpredictable substrates.

Yet the water bear, a micro-animal so distinct that scientists were forced to assign it to its own phylum, uses eight stubby legs to improbably propel itself through marine and freshwater sediment, across desert dunes, and beneath the soil.

The new discovery of how tardigrades walk implies the existence of either a common ancestor or an evolutionary advantage that explains why one of the smallest and squishiest creatures evolved to walk just like larger, hard-bodied insects.

Tardigrades have a robust and clear way of movingtheyre not these clumsy things stumbling around in the desert or in leaf litter, says Jasmine Nirody, a fellow in Rockefeller Universitys Center for Studies in Physics and Biology. The similarities between their locomotive strategy and that of much larger insects and arthropods opens up several very interesting evolutionary questions.

Nirody and colleagues first determined how water bears walk and run. If you watch tardigrades under a light microscope for long enough, you can capture a wide range of behavior, Nirody says. We didnt force them to do anything. Sometimes they would be really chill and just want to stroll around the substrate. Other times, theyd see something they like and run towards it.

Nirody found that, at their most leisurely, water bears lumber about half a body length per second. At full throttle, their loping strides carried them two body lengths in the same amount of time.

Tardigrades are an important porthole into soft-bodied, microscale locomotion.

But the surprise came when she observed how a water bears feet contact the ground as it gains momentum. Unlike vertebrates, which have distinct gaits for each speedpicture a horses hooves as it transitions from a walk to a galloptardigrades run more like insects, scurrying at increasing speeds without ever changing their basic stepping patterns.

When vertebrates switch from walking to running, there is a discontinuity, Nirody says. With arthropods, all stepping patterns exist along the same continuum.

Why do tardigrades share a locomotive strategy with much larger, hard-bodied insects?

One possible explanation is that tardigrades, long assumed to fit neatly into no existing taxonomy, may share common ancestorsand even a common neural circuit with insects such as fruit flies, ants, and other segmented scurrying creatures. In fact, some scientists advocate classifying tardigrades within the proposed panarthropod clade, a catchall group that would assign common shelf space to insects, crustaceans, velvet worms, and water bears.

Another possibility is that there is no ancestral connection between tardigrades and arthropods, but that the unrelated groups of organisms independently arrived at the same walking and running strategies because they were evolutionarily advantageous. Perhaps the best way to navigate unpredictable terrain with a microscopic body is to plod like a water bear.

Nirody is equally fascinated by both possibilities. If there is some ancestral neural system that controls all of panarthropod walking, we have a lot to learn, she says. On the other hand, if arthropods and tardigrades converged upon this strategy independently, then theres much to be said about what makes this strategy so palatable for species in different environments.

Beyond the implications for evolutionary biology and the study of animal locomotion, the findings may have ramifications for the burgeoning fields of soft and microscale robotics.

By studying how small animals evolved to move across challenging environments, scientists may be able to design robots that can more efficiently squeeze into small spaces or operate at the microscale.

We dont know much about what happens at the extremes of locomotionhow to make an efficient small walker, or how soft-bodied things should move, Nirody says. Tardigrades are an important porthole into soft-bodied, microscale locomotion.

The new study appears in the Proceedings of the National Academy of Sciences.

Source: Rockefeller University

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Teeny 'water bear' walk points to evolution mystery - Futurity: Research News

Deep beneath the rubble and ashes of Chicagos Cabrini-Green lies a secret. Its history is written on the very souls of its last remaining residents, always lurking behind them. His face may change over time, but the name will always be remembered, along with that bloody hook. After almost 30 years since his original summoning, Candyman returns with new blood behind the camera.

Written by Jordan Peele and directed by Nia DaCosta, this sequel steps deeper into the hive of racial hatred and social commentary to uncover truths its predecessor could never achieve. Serving as both a direct sequel but also a fresh reboot, it is more than just a retelling. The entire craft is renovated with the most calculated execution. The themes are expanded, the symbolism is perfected and with a sprinkle of Peeles comedic timing, the scares are just as effective. Looking at every element of the 1992 classic, Candyman serves as the perfect sequel.

Peeles screenplay evolves the original story in a fresh perspective, giving the victims the voice rather than an outsider peeking through the blinds. Peele also utilizes this shift as an opportunity to redeem his own craft: he finally got the chance to write the ending he wanted to make for Get Out. Real life tragedy rots into cathartic horror, swarming around you to feed on your skin. It is a jaw-dropping experience, spared to the very end as a mic drop to audiences worldwide. It is because of the final scene that Peele achieves the true symbolism of the Candyman even better than its creator, Clive Barker.

With the original towers of Cabrini-Green long gone, one of the recurring themes is the cultural destruction of gentrification. What was once discarded brick and graffiti is now painted over white with clean furnishings. This re-polishing of Cabrini-Greens ghetto is where DaCostas directing shines, because the film itself can be seen as a gentrification of its predecessor. She takes the floating camerawork of the 1992 classic to new levels, sweeping through the streets of Chicago as if on the prowl for its next meal. Peele himself favored her directing over his, seeing it as refined, elegant, which can be the coinable term for not only the neighborhoods new apartments, but the main protagonist himself. He starts as a sculpted artist, distanced from his work with a clean conscience, but once the truth of his own soul is unmasked, he sinks deeper into the floors until it stains his very skin. The gentrified imagery lingers in the background, suffocating Cabrini-Green and serving as the true opposing force inside the walls.

Near the end of the story, the film begins to trip on its own inspiration. 1992s Candyman was more of a prophetic voice seeking direct revenge rather than a true force of nature, so even though Peeles evolved symbol in the hook resonates long after the credits roll, the plot decides to curve its momentum for a more faithful conflict. A contrived twist that squashes the true scale of what the themes were trying to achieve, which is very similar to the ending of its predecessor.

If this film had the chance to be released when it was supposed to, it would be just as influential and timeless as Get Out. Sadly, with it only coming out in theaters rather than streaming, I dont see it gaining any longstanding following. Its a fun watch with beautiful visuals and a great revival of the original score, enough to pick up the slack when the plot falters. From beginning to end, it sinks its hook into your heart, and with a chilling voice, whispers, Say my name.

Title: Candyman

Starring: Yahya Abdul-Mateen II, Teyonah Parris, Colman Domingo

Director: Nia DaCosta

If you like: Get Out, Lovecraft Country

Shamrocks: 4 out of 5

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'Candyman': Resurrection, evolution and gentrification - Observer Online

The discussion of cannabis strains has evolved to a point where it can feel like an entirely foreign language. While most consumers are familiar with the bedrock categories of sativa, indica and hybrids, concepts like minor cannabinoids and terpene profiles have expanded the conversation dramatically. Additionally, the sheer volume of strains on the market today can make the experience of selecting the best option for your needs feel downright overwhelming.

Fortunately, getting a better grasp on exactly what makes a strain a strain can be as simple as taking a quick journey through cannabis history. To start, lets take a closer look at the aforementioned bedrock strains.

While mainstream cannabis culture has long relied on sativa, indica and hybrids to define a given strain, these terms are largely considered outdated. For many years, common wisdom suggested that sativas offered a more cerebral high while indicas, by contrast, would put consumers in da couch, courtesy of a body high. Hybrids, by extension, offered varying combinations of the two.

This line of thinking can be traced back to the mid-1700s, where the terms indica and sativa were separately established as cannabis subspecies by Swedish botanist Carl Linneaus and French biologist Jean-Baptiste Lamarck. Though far less prevalent, it should also be noted that a third subspecies, ruderalis, was identified by Russian botanist Dmitrij Janischewsky in 1930. Owing to the murky taxonomy of cannabis a situation undoubtedly exacerbated by the fact that cannabis was illegal in most of the world until recently indica and sativa caught on while ruderalis became more of a historical footnote.

Whats important to understand is that these terms are botanical in nature, not pharmacological. Rather than telling us about the potential effects that come with consuming a sativa or indica, these categories speak to the shape and size of a given cannabis plants leaves and the fiber they produce. In short, these concepts remain helpful to cultivators but do little to give consumers a clear picture of what they can expect to experience.

Fast forward to the 1960s, and we arrive at the onset of modern cannabis breeding.

As demand for cannabis in the U.S. continued to grow, the longer flowering cycle required of the pure sativas grown and transported from Mexico and the Caribbean caused a lack of supply. In search of a solution, California cannabis breeders began crossing these sativas with indicas native to Nepal and Afghanistan, hoping to create strains that offered the quicker flowering cycle of the latter with the higher potency of the former. Their success would ultimately establish Californias position as a capital for world-class cannabis while also kicking off a hybrid cultivating craze that continues to this day.

Naming conventions for cannabis strains can also be pegged to this milestone moment.

Prior to the 1970s, strains were usually named for the geographic region in which they originated. Also known as landrace strains, this straightforward process resulted in mainstays like Panama Red, Afghan Kush, and Acapulco Gold. From there, these strains were crossed, and then those crosses were crossed, and so forth. As a means of establishing lineage, subsequent strains were named to reflect the parent strains of a given hybrid.

Today, however, strain names are inspired by a variety of factors. In some cases, the name may speak to the strains effects, while others may highlight a given strains notable coloring, trichome density or aroma. And then there are strains named for pop culture figures, cannabis icons, and in some cases, just whatever the breeder in question felt like using. As a result, while some names can tell us a lot about a given strain though even that can vary from market to market going off name alone is not always a reliable metric.

Instead, most budtenders will likely tell you about a strains terpene profile and featured cannabinoids. Unlike strain names, knowing the amount and type of terpenes and cannabinoids a strain contains is an excellent method for determining which options will work best for you.

As cannabis breeding continues to diversify the strain pool, its never been more important to ensure that cultivators have access to the seeds that make it all possible. Thankfully, we have seed banks.

Seed banks are businesses that specialize in storing and selling cannabis seeds. With many showcasing incredibly robust inventories, seed banks can be seen as a kind of living library for the flowers genetics, featuring both classic options as well as the latest and greatest.

In addition, seed banks will often feminize the seeds they sell an incredibly important facet of the process considering its only the female cannabis plant that can produce the buds we know and love. Some seed banks also offer whats known as auto-flowering seeds, which some growers may prefer as the resulting plants mature quickly and produce maximum yields.

Lastly, its important to note that the story of strains is still being written. As advances in genetic mapping continue to evolve, its possible our understanding of strains will dramatically expand in the months and years to come. But for now, with the above information in mind, you should feel fully empowered to begin your own strain quest in search of the perfect match.

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A Guide to the Evolution of Cannabis Strains - Cannabis Now

The hatchlings of the invasive cane toad in Australia don't stand a chance against their deadliest predator: cannibal tadpoles who guzzle the hatchlings like they're at an all-you-can-eat buffet. But now, the hatchlings are fighting back.

They're developing faster, reducing the time that hungry tadpoles have to gobble them up, a new study finds.

"If cannibals are looking for you, the less time you can spend as an egg or hatchling, the better," said study lead researcher Jayna DeVore, who did the research as a postdoctoral research associate at the University of Sydney and is now a biologist for the Tetiaroa Society, a nonprofit conservation organization in French Polynesia.

Developing quickly, however, has its pitfalls. Compared with typically growing hatchlings, those that grew faster fared worse when they reached the tadpole stage of life, the researchers found. So it isn't "worth it to try to defend yourself in this way unless cannibals are definitely coming for you," DeVore told Live Science.

Related: Image gallery: Invasive species

The cane toad (Rhinella marina) is a poster child for invasive species. The warty toxic toad, notorious for gulping down anything that fits into its wide mouth, is native to South America. In the 1930s, farmers in Queensland, Australia, thought the toad would be the perfect predator to gobble up beetles that were destroying sugarcane fields. But with no natural predators Down Under, the toad population ballooned from only 102 individuals to more than 200 million, according to WWF Australia.

Another reason for their population spike is that female toads can lay more than 10,000 eggs at a time in small ponds. "When these eggs first hatch, the young can't swim or eat yet, so they can pretty much only lie there on the bottom of the pond until they develop into tadpoles," DeVore said.

The hungry tadpoles strike during this vulnerable hatchling period. "Once the hatchlings develop into tadpoles, they are too large and mobile for other tadpoles to eat them, so the cannibals have to work quickly if they want to consume them all," DeVore said.

Tadpoles that cannibalize the younger generation are doing themselves a huge favor; they're getting nutrients and eliminating later competition for resources. "When I first saw this behavior in the wild, I was amazed at how voraciously cane toad tadpoles sought out cane toad hatchlings and ate them," DeVore said. To determine whether this behavior was "normal" or whether it was an adaptation to extreme competition among invasive cane toads, DeVore and her colleagues compared Australia's invasive cane toads with the native-range ones, or cane toads from their indigenous regions.

Several experiments revealed that the invasive toads both the hatchlings and the cannibalistic tadpoles are evolving at breakneck speed.

In one experiment done more than 500 times with different individuals, DeVore and her colleagues placed one tadpole in a container with 10 hatchlings. Although the native-range tadpoles did engage in some cannibalism, "we found a hatchling was 2.6 times as likely to be cannibalized if that tadpole was from Australia than if it was from the native range," she said.

Moreover, the invasive tadpoles were much more attracted to the hatchlings than the native tadpoles were. In another experiment, the team placed tadpoles in a pool with two traps; one trap held hatchlings, and the other was empty. "In Australia, the cannibalistic tadpoles were attracted to the hatchlings; the odds that an Australian tadpole would enter the trap containing hatchlings were about 30 times those of it entering the empty trap," DeVore said.

Related: Survival of the grossest: 8 disgusting animal behaviors

In contrast, the native-range "tadpoles were not attracted to the hatchlings; they were just as likely to enter the empty trap as the hatchling trap," she said. "This demonstrated that this strong attraction to the vulnerable hatchling stage, which is what helps the cannibalistic tadpoles to detect and locate their victims in Australia, is not present in the native range."

To fight back, invasive hatchlings have evolved an escape strategy. When the researchers compared the time eggs and hatchlings spent developing, they found that the invasive toads developed faster than the native-range ones.

In both groups, "we found that cane toad clutches from Australia developed more quickly; they reached the invulnerable tadpole stage in about four days, whereas native range clutches took about five days," DeVore said.

In addition, the invasive hatchlings had a more "plastic," or flexible response than the natural-range hatchlings when a cannibal tadpole was present; the hatchlings from Australia were "more likely to be able to smell when cannibals are around and actually accelerate their development in response," DeVore noted.

While these strategies helped the hatchlings survive, they paid for it later. The researchers tested 1,190 tadpoles for survival, development, growth and plasticity, and found that those that developed faster as eggs and hatchlings to escape cannibalism fared worse and developed more slowly at the tadpole stage than the native-range tadpoles, the team found.

Could the cane toads eat themselves into extinction? Probably not, DeVore said.

"Australian cane toads may well be their own worst enemy, but I wouldn't expect them to go extinct anytime soon," she said. That's because the cannibals benefit too much from eating their own kind. After gaining nutrients and limiting competition, the cannibalistic tadpoles "transform into toads more quickly and at a larger size," she said. It's even possible that these "successful" toads will more rapidly invade new places in Australia.

"The good news is that cannibalism can control population growth," DeVore said. "So, although cane toads are unlikely to drive themselves extinct, these cannibalistic behaviors may help to regulate their abundance post-invasion."

The study was published in the Aug. 31 issue of the journal Proceedings of the National Academy of Sciences.

Originally published on Live Science.

Link:

Cannibal toads eat so many of their young, they're speeding up evolution - Livescience.com

Image credit: Robert W. Booessenecker, CC BY-SA 4.0 , via Wikimedia Commons.

The media are currently abuzz with claims of a newly discovered fossil from Egypt: a four-legged whale. Here are some prominent headlines:

And so on. The headlines are accompanied by an artists depiction of what was supposedly found. See above. The image is attributed to one of the co-authors of thetechnical paper, geologistRobert W. Boessenecker.

The NPR story warns:

We regret to inform you that your nightmares are about to get worse.

A team led by Egyptianscientistshave dug up a 43 million-year-old fossil in the Sahara Desert in Egypt of a now-extinct amphibious four-legged whale.

Thats right, folks a whale with legs.

The problem with these claims? Thats right folks they didnt find any of the fossils legs. Everything you just read about this fossil is the product of imagination. In fact, if you check thetechnical paperyoull learn that they found very little of the fossil at all. Figure 1 from the paper, whichcan be seen online here, shows the bones that were discovered shaded in red. Zoom in and look at the drawing in the middle. You may notice, as I said, a curious absence of red-shaded leg bones.

Also absent: the pelvis, the vast majority of ribs and vertebrae, and the front portion of the snout. Undoubtedly the organism had these bones, but to call this a whale with legs, or to unequivocally depict it as some species transitional between terrestrial mammals and whales (as seen above), is to impose a huge amount of evolutionary imagination on the situation.

Consistent with all of this, the paper notes in the abstract that what they did find was a partial skeleton, later stating, The new species is based on a partial skeleton. A complete description of the bones is provided later in the paper as follows:

an associated partial skeleton of a single individual including the cranium, the right mandible, incomplete left mandible, isolated teeth, the fifth cervical, and the sixth thoracic vertebrae and ribs. The holotype is the only known specimen.

Perhaps this organism had four legs. Perhaps it had flippers. Perhaps it was closely related to whales. Perhaps it has nothing to do with whales. No one really knows. The simple fact of the matter is that we know hardly anything about this creature because, again, so very little of it was found. Forcing this species into an evolutionary paradigm to fit preconceived ideas about cetacean evolution, and promulgating headlines about a four-legged whale, is beyond belief. Actually, I take that back. Belief belief in an evolutionary paradigm is the thing thats driving these headlines.

Imagination. Belief. Thats putting it politely, which I insist upon doing. We all have imaginations, and we all have beliefs. So in that sense this is understandable. But if I werent so polite, a variety of other terms could be used to describe telling the public this fossil represents a four-legged whale.

Is it any wonder that people dont trust overhyped evolutionary claims made by the media, or by some scientists?

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Evolutionary Imagination and Belief Drive False Claims of a Four-Legged Whale - Discovery Institute

Inkay is a Psychic & Dark Pokemon recently launched in Pokemon Go. While the Pokemon is vulnerable to Fairy and Bug moves, its deals maximum damage through attacks like Night Slash and Tackle. The Pokemon can also be evolved into Malamar with 50 candies. Inkay and its evolutionary form Malamar are making their debuts in Pokemon Go during the Psychic's Spectacular event which will begin on Wednesday, September 8, 2021, at 10 AM local time to Monday, September 13, 2021, at 8 PM local time.

As mentioned on the PokemonGoLive website, trainers can complete themed Field Research Tasks in order to encounter event-themed Pokemon like Woobat, Inkay and more. When the event begins on September 8, 2021, Inkay-themed Field Research Tasks must be revealed in the game. On completing such tasks, a trainer would be rewarded an encounter with Inkay. Additionally, a trainer might encounter the Pokemon in the wild.

Inkay and its Evolution, Malamar, will be making their Pokmon GO debuts! Inkay will evolve only under unique circumstances. Trainers who have journeyed through the Kalos region inPokmon XandPokmon Ymay have an inkling as to what those circumstances might be! ~ Pokemon Go Live blog post

As stated earlier, Inkay will be available in the wild, through Field Research Tasks and in one-star raids. While the general spinning at the PokeStops and applying incense might work, players must be prepared to catch the Pokemon as and when one appears in the wild, or in one-star raids. The Pokemon is weak Fairy and Bug Type Pokemons, which deal 160% and 256% damage to the Pokemon respectively.

By completing themed Field Research tasks, you can encounter event-themed Pokmon like Woobat, Inkay, and more. ~ Pokemon Go Live blog post

Inkay can be evolved into Malamar with the help of 50 Candies. Malamar is also a Psychic & Dark Pokemon which is vulnerable to Fairy and Bug moves. Its strongest moves are Foul Play and Psycho Cut. The Pokemon has a maximum CP of 2,359. It is slightly difficult to evolve Inkay in Malamar as the candies might be tricky to collect. Whether Malamar will be available as a form is unclear, and how to catch Malamar is not clear.

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How to catch Inkay in Pokemon Go? Check evolution guide to Malamar & where to find tips - Republic World

Australian sugarcane farmers began using cane toads (Bufo marinus) as a form of pest control in their fields in 1935but soon enough, they became a pest themselves. The warty amphibian with thick ridges above their eyes and highly poisonous olive-brown skin devours anything it can fit in its mouth from tiny rodents to birds. When the toads became established in the country, the species had no natural predators. The invasive species has since expanded its reach across large areas of Northern and Eastern Australia with more that 200 million cane toads hopping around the country, reports Nature's Max Kozlov.

Without predation to keep population numbers low, cane toad tadpoles began to eat their peers, reports Ars Technica's John Timmer. The cannibalistic behavior appears to be an evolutionary response to the toad not having another competing species, causing the toads to turn on the only species competing for resources: themselves.

However, researchers at the University of Sydney have found that tadpoles are evolving ways to avoid becoming a snack, such as developing at faster rates to reduce the amount of time they are vulnerable to other ravenous tadpoles, reports Laura Geggel for Live Science. The study was published this week in the peer-reviewed journal Proceedings of the National Academy of Sciences.

In the species' native South American habitat, cane toad tadpoles have previously been observed eating their peers. However, cannibalistic behavior occurs more often in Australia. To see if the behavior results in differences between native and invasive species populations, researchers gathered toads from South America and Australia and bred them. Then, they introduced one large tadpole to a group of ten tiny hatchlings just emerged from their eggs. The team discovered Australian tadpoles were 2.6 times more likely to cannibalize hatchlings than South American tadpoles, Nature reports. But once hatchlings were too big to be cannibalized, the older tadpoles left them alone. Similarly, older tadpoles did not have an appetite for other tadpoles their size and age.

While South American toads spent five days at the hatchling stage, Australian toads only spend three days in this stage, suggesting that the pressures from being cannibalized cut their development time by half, per Ars Technica.

"We found that cane toad clutches from Australia developed more quickly; they reached the invulnerable tadpole stage in about four days, whereas native range clutches took about five days," says study author Jayna Devore, a University of Sydney herpetologist, to Live Science.

The find may give researchers an understanding of how competition within a species ignites an evolutionary arms race and drives rapid evolution.

"The good news is that cannibalism can control population growth," DeVore tells Live Science. "So, although cane toads are unlikely to drive themselves extinct, these cannibalistic behaviors may help to regulate their abundance post-invasion."

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Without Predators, Cannibalistic Cane Toads Eat Their Youngand It's Rapidly Accelerating the Species' Evolution - Smithsonian Magazine

Significance

Invasive species are known for their ability to achieve high densities within their introduced range. Hence, invaders often face strong competition from members of their own species. Mechanisms for reducing intraspecific competition may therefore be favored in invasive populations, such as cannibalism, in which individuals kill and eat intraspecific competitors. Here, we find that toad tadpoles from invasive Australian populations have evolved both a strong behavioral attraction to the vulnerable hatchling stage and an increased propensity to cannibalize these younger conspecifics. In response, these toads have also evolved multiple strategies for reducing the duration of the vulnerable period, indicating an evolutionary arms race between the cannibalistic tadpole stage and the vulnerable egg and hatchling stages in invaded habitats.

Biotic conflict can create evolutionary arms races, in which innovation in one group increases selective pressure on another, such that organisms must constantly adapt to maintain the same level of fitness. In some cases, this process is driven by conflict among members of the same species. Intraspecific conflict can be an especially important selective force in high-density invasive populations, which may favor the evolution of strategies for outcompeting or eliminating conspecifics. Cannibalism is one such strategy; by killing and consuming their intraspecific competitors, cannibals enhance their own performance. Cannibalistic behaviors may therefore be favored in invasive populations. Here, we show that cane toad tadpoles (Rhinella marina) from invasive Australian populations have evolved an increased propensity to cannibalize younger conspecifics as well as a unique adaptation to cannibalisma strong attraction to vulnerable hatchlingsthat is absent in the native range. In response, vulnerable conspecifics from invasive populations have evolved both stronger constitutive defenses and greater cannibal-induced plastic responses than their native range counterparts (i.e., rapid prefeeding development and inducible developmental acceleration). These inducible defenses are costly, incurring performance reductions during the subsequent life stage, explaining why plasticity is limited in native populations where hatchlings are not targeted by cannibalistic tadpoles. These results demonstrate the importance of intraspecific conflict in driving rapid evolution, highlight how plasticity can facilitate adaptation following shifts in selective pressure, and show that evolutionary processes can produce mechanisms that regulate invasive populations.

All data are available in the Supplementary Materials. Note that a subset of the invasive range data used here were also used in DeVore et al. 2021; here we incorporate these results into larger datasets to make comparisons between the native and invasive range.

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The evolution of targeted cannibalism and cannibal-induced defenses in invasive populations of cane toads - pnas.org

Itd be easy to get the impression that realtime 3D is really coming of age. For a long time, all computer graphics looked like well Tron, at best, and often not nearly as slick.

Then pre-rendered 3D started looking good enough for things like spaceships, and now were able to clamber almost (but not quite) all the way out of the uncanny valley in which CG humans have often lived. Realtime CG renderers have not been idle, of course, and ever since 2007s seminal Crysis, Nvidia and AMD, and the people who write the code, have been pushing hard to make video games look as good as movies.

And havent they? Were now using code written to draw video games, things like Unreal Engine, to produce graphics for LED volumes that were expecting to look photorealistic. OK, that doesnt often involve human beings, but recent releases such as Cyberpunk 2077and Watch Dogs: Legion are both, if occasionally, capable of producing scenes capable of provoking a fleeting impression of a real city being just the other side of the thin film transistors. Isnt this convergence; can we expect to see a future in which the difference between pre-rendered and realtime 3D becomes irrelevant?

Well, maybe, but this isnt it. Until very recently, video games invariably used what was fundamentally a development of techniques going decades. First, we started making 3D objects out of triangles. Why triangles? Because no matter where we put three points in space, they always describe a two-dimensional, flat area. At first, the triangles werent even filled in wireframe graphics you could see straight through. Next, we figured out things looked better if we filled them in solid. Then we started sticking bits of image data onto those triangles, so that theyd have some texture, and about the same time started taking notice of where virtual light sources were in the scene to make the triangles brighter or darker.

That level of technology worked out okay through the 2000s, but there are some obvious things it didnt do, things that pre-rendered 3D could. Until recently video games couldnt show accurate reflections they could sometimes do something that sort of looked like a reflection of the environment in a chrome surface, but look closely, and it was just a fixed image that didnt represent changes in the environment thats being reflected. They also didnt show shadows, at least not without a lot of workarounds, and shadows of unmoving objects such as terrain and buildings were pre-rendered into images then pasted onto the triangles to simulate light and shadow.

That creates on good example of the sort of limitations realtime 3D engines often impose in order to achieve what they do. Ever wonder why you cant blow up walls in the average first-person shooter? Because, at least in part, the pre-rendered lighting stops being valid if you move a large shadow-casting object out of the way. Maya (or its renderer) renders that sort of things fresh, every frame, or at least it can if it needs to.

Still, combine all those reasonable-looking but actually very inaccurate tricks together, evolve for ten or fifteen years, and we get Crysis. It should be very clear, though, that a lot of shortcuts are involved. That spectacular mountain range? A fixed background image; you can never go there. The fine detail on your sci-fi rifle? The rivets are clever types of image mapping, so dont look too close. That mountainside full of trees? Geometry instancing allows the system to use multiple copies of the same tree, scaled and rotated and scattered. Statue reflected in a pool of water? Thats the time-honoured technique of taking the picture of the statue, flipping it upside down, and relying on the irregular surface of the water to hide the fnords.

Problems occur with that statue if, for instance, we cant see the top of the statue because were looking down at the water, but we should be able to see the reflection of the top of the statue. We cant flip an image we havent rendered. Basically, video games cheat. A lot. Thats fine, when it works. The problem is that all the workarounds become more work than doing it properly.

Define properly? Well, for a short while, since, say, the release of Nvidias RTX series, games have been at capable of cheating slightly less, through ray tracing. Situations like that reflecting pool become a little more reliable if we actually work out where the rays of light would go for real. Its easier conceptually, if not computationally, and lots of workarounds are still required. One workaround that should be recognisable to prerendered CG people is noise reduction, based on the fact that we cant sample every ray from of every light for every pixel on the screen. We sample a random selection, which gives us a noisy image, and we apply noise reduction.

And that is something thats very much in common with the approaches used by conventional 3D graphics software. With that and ray tracing, theres certainly growing commonality between realtime and non-realtime renders, and therefore no surprise that things seem like theyre starting to converge. What we need to recognise is that the scope and scale of what realtime 3D can do is necessarily limited, for all of the reasons weve considered here. In 2021, were some way from being able to create arbitrarily large and complex scenes and accurately simulate all of the lighting in realtime in the way we can in software like Cinema 4D, where itll have some time to go away and think about things.

Still, its hard to complain that some of the most respected television currently in production is using technology that was unequivocally built to bring Playstation owners joy, and with great success. Without video games, wed have no GPU processing, no realtime LED volumes, and, most importantly of all, no Cyberpunk 2077. Ill be busy for the next hour or so.

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The battle for realism: The evolution of realtime 3D graphics - RedShark News