The lush biodiversity of South America's rainforests is rooted in one of the most cataclysmic events that ever struck Earth.
- One especially mysterious thing about the asteroid impact, which killed the dinosaurs, is how it transformed Earth's tropical rainforests.
- A recent study analyzed ancient fossils collected in modern-day Colombia to determine how tropical rainforests changed after the bolide impact.
- The results highlight how nature is able to recover from cataclysmic events, though it may take millions of years.
About 66 million years ago, a massive asteroid slammed into present-day Chicxulub, Mexico, triggering the extinction of dinosaurs. Scientists estimate the impact killed 75 percent of life on Earth. But what's remained more mysterious is how the event shaped the future of plant life, specifically tropical rainforests.
A new study published in Science explores how the so-called bolide impact at the end of the Cretaceous period paved the way for the evolution of our modern rainforests, the most diverse terrestrial ecosystems on Earth.
For the study, researchers analyzed thousands of samples of fossil pollen, leaves, and spores collected from various sites across Colombia. The researchers analyzed the samples to determine which types of plants were dominant, the diversity of plant life, and how insects interacted with plants.
All samples dated back to the Cretaceous-Paleogene boundary, some 70 million to 56 million years ago. Back then, the region's climate was mostly humid and hot, as it is today. However, the composition and structure of forests were quite different before the impact, according to the study results.
Tropical jungle with river and sun beam and foggy in the gardenSASITHORN via Adobe Stock
For one, the region's rainforests used to have a roughly equal mix of angiosperms (shrubs and flowering trees) and plants like conifers and ferns. The rainforests also had a more open canopy structure, which allowed more light to reach the forest floor and meant that plants faced less competition for light.
What changed after the asteroid hit? The results suggest the impact and its aftermath led to a 45 percent decrease in plant diversity, a loss from which the region took about 6 million years to recover. But different plants came to replace the old ones, with an increasing proportion of flowering plants sprouting up over the millennia.
"A single historical accident changed the ecological and evolutionary trajectory of tropical rainforests," Carlos Jaramillo, study author and paleopalynologist at the Smithsonian Tropical Research Institute in Panama City, told Science News. "The forests that we have today are really the by-product of what happened 66 million years ago."
Today's rainforests are significantly more biodiverse than they were 66 million years ago. One potential reason is that the more densely packed canopy structure of the post-impact era increased competition among plants, "leading to the vertical complexity seen in modern rainforests," the researchers wrote.
The extinction of long-necked, leaf-eating dinosaurs probably helped maintain this closed-canopy structure. Also boosting biodiversity was ash from the impact, which effectively fertilized the soil by adding more phosphorus. This likely benefited flowering plants over the conifers and ferns of the pre-impact era.
In addition to unraveling some of the mysteries about the origins of South America's lush biodiversity, the findings highlight how, even though life finds a way to recover from catastrophe, it can take a long time.
Ultimately, this is a fight between a giant reptile and a giant primate.
The 2021 film “Godzilla vs. Kong" pits the two most iconic movie monsters of all time against each other. And fans are now picking sides.
Even the most fantastical creatures have some basis in scientific reality, so the natural world is a good place to look to better understand movie monsters. I study functional morphology – how skeletal and tissue traits allow animals to move – and evolution in extinct animals. I am also a huge fan of monster movies. Ultimately, this is a fight between a giant reptile and a giant primate, and there are relative biological advantages and disadvantages that each would have. The research I do on morphology and biomechanics can tell us a lot about this battle and might help you decide – #TeamGodzilla or #TeamKong?
Larger than life
First it's important to acknowledge that both Kong and Godzilla are definitely far beyond the realms of biological possibility. This is due to sheer size and the laws of physics. Their hearts couldn't pump blood to their heads, they would have temperature regulation problems and it would take too long for nerve signals from the brain to reach distant parts of the body – to name just a few issues.
However, let's assume that somehow Godzilla and Kong are able to overcome these size limitations – perhaps because of their radiation exposure they have distinctive mutations and characteristics. Based on how they look on the big screen, let's explore the observable differences that might prove useful in a fight.
Kong: the best of ape and human
At first glance, Kong is a colossal primate - but he's not simply a giant gorilla.
Cliff/Wikimedia Commons, CC BY
One of the most striking things about Kong is his upright, bipedal stance – he mostly walks on two legs, unlike any other living nonhuman apes. This ability could suggest close evolutionary relationship to the only living upright ape, humans – or his upright stance could be the result of convergent evolution. Either way, like us, Kong has thick muscular legs geared toward walking and running, and large free arms with grasping hands, enabling him to use tools.
Humanity's bipedal, upright posture is unique in the animal kingdom and provides a slew of biomechanical abilities that Kong might share. For example, human torsos are highly flexible and particularly good at rotation. This feature – in addition to our loose shoulder girdle – makes humans the best throwers in the animal kingdom. Throwing is helpful in a fight, and Kong could probably throw with the best of them.
Kong is also, of course, massive. He absolutely dwarfs the largest known primate, an extinct orangutan relative called Gigantopithecus that was a bit bigger than modern gorillas.
Kong does have many gorillalike attributes as well, including long muscular arms, a short snout with large canine teeth, and a tall sagittal crest – a ridge of bone on his head that would be the anchor point for some exceptionally strong jaw muscles.
Strong, agile, comfortable on land and with the unparalleled ability to use tools and throw, Kong would be a brutal force in a fight.
Kenneth Carpenter/Wikimedia Commons, CC BY-SA
Godzilla: An aquatic lizard to be reckoned with
Godzilla appears to be a giant, semiaquatic reptile. Like Kong, Godzilla has the traits of a few different species.
Recent Godzilla movies show him decently mobile on land, but seemingly much more comfortable in the water despite his lack of overt aquatic features. Interestingly, Godzilla is depicted with gills on his neck – a trait that land vertebrates lost after they emerged from the sea about 370 million years ago. Given Godzilla's terrestrial features, it's likely that his species has land-dwelling reptile ancestors and reevolved a mostly aquatic lifestyle – kind of like sea turtles or sea snakes, which can actually absorb oxygen through their skin in water. Godzilla may have uniquely reevolved gills.
Godzilla's tail is what really separates him from Kong. It is massive, and anchored and moved by huge muscles attached to his legs, hips and lower back. Dinosaurs like Tyrannosaurus rex stood horizontally and used their tails for balance and to help them walk and run. Godzilla, in contrast, stands vertically and keeps his tail low to the ground, probably for a different type of balance. This vertical posture is unique for a two-legged reptile and more resembles a standing kangaroo. Godzilla stands on two muscular, pillarlike legs similar to those of a sauropod dinosaur. These would provide stability and help support his gargantuan mass but would also bolster the strength of his tail.
In addition to his powerful tail, Godzilla carries three rows of sharp spikes going down his back, thick scaly skin, a relatively small head full of carnivorous teeth and free arms with grasping hands, all built onto a muscular body. Taken together, Godzilla is a terrifying and intimidating adversary.
Tim Simpson/Flickr, CC BY-NC
So now that we've looked a little closer at how Godzilla and Kong are built, let's imagine who might emerge victorious in battle.
Though Kong is a little bit smaller than Godzilla, both are more or less comparably massive in size and neither has a clear advantage here. So what about their fighting abilities?
Godzilla would likely favor his robust tail for both offense and defense – much like modern-day large lizards that use their strong tails as whips. Scale up that strength to Godzilla's size, and that tail becomes a lethal weapon – which he has used before.
However, Kong is more comfortable on land, faster and more agile, can use his strong legs to jump, and possesses much stronger arms than Godzilla – Kong probably packs a walloping punch. And as an ape, Kong would also likely use tools to some degree and might even capitalize on his throwing ability.
Both would have a gnarly bite, with Kong likely getting a slight advantage. However, Godzilla's bite is by no means weak, and all of his teeth are flesh-piercing, similar to crocodile and monitor lizard teeth.
On defense, Godzilla has the edge, with thick scaly skin and sharp spikes. He might even act like a porcupine, turning his back to a rapidly approaching threat. However, Kong's superior agility on land should be able to offer him some protection as well.
I will admit I am #TeamGodzilla, but it's very close. I may give a slight edge to Kong in broad terrestrial battle ability, but Godzilla's general mass, defense and tail would be hard to overpower. And lest we forget, the tipping point for Godzilla is that he has atomic breath! Until researchers find evidence of a dinosaur or animal with something like that, though, I will have to reserve my scientific judgment.
Regardless of who emerges victorious, this battle will be one for the ages, and I am excited as both a scientist and monster movie fan.
This article has been updated to use more inclusive language.
Kiersten Formoso, PhD Student in Vertebrate Paleontology, USC Dornsife College of Letters, Arts and Sciences
Fossils of ancient creatures doing anything are rare. This one is absolutely unique.
- A new fossil from southern China shows a dinosaur incubating its eggs at the time of its death.
- The find sheds light on oviraptor eating and egg-tending behavior.
- The find will be the focus of further study for some time.
Despite how many of them you can find at a museum, fossils are comparatively rare. They can only form when a plant or animal dies under certain conditions, and without them the remains are typically lost to time. These limitations mean that fossils depicting ancient creatures doing things (like fighting) are extremely difficult to find and are all the more important when discovered.
A new fossil showing a dinosaur's behavior has recently been discovered in Ganzhou, China giving insights into how the oviraptor tended to its eggs and perhaps even shedding light on its development.
Credit: Zhao Chuang / PNSO
The fossil depicts a large dinosaur sitting on a clutch of at least 24 eggs in a manner not unlike that of a bird. At least seven of the eggs contain fossilized embryos with the skeletons of the unhatched oviraptor. The apparently late level of development of these eggs combined with the lack of sediment between the bones and the eggs suggests that the oviraptor may have been incubating its nest when it died.
"Dinosaurs preserved on their nests are rare, and so are fossil embryos. This is the first time a non-avian dinosaur has been found, sitting on a nest of eggs that preserve embryos, in a single spectacular specimen," explains lead author Dr. Shundong Bi.
Co-author Dr. Matthew Lamanna also commented on how rare and exciting this find is:
"This kind of discovery, in essence fossilized behavior, is the rarest of the rare in dinosaurs. Though a few adult oviraptorids have been found on nests of their eggs before, no embryos have ever been found inside those eggs. In the new specimen, the babies were almost ready to hatch, which tells us beyond a doubt that this oviraptorid had tended its nest for quite a long time. This dinosaur was a caring parent that ultimately gave its life while nurturing its young."
The fossil in question, notice the open sections of the blue green eggs.
Credit: Shundong Bi
While this small pile of bones may not look impressive to you, it is a proverbial goldmine of information for paleontologists, shedding light on dinosaur behavior in ways that other fossils can't come close to.
The parent—it is not currently known if it was male or female—clearly had gastroliths, also called "stomach stones," in its abdominal region. Commonly consumed by animals to help grind foods they cannot fully process with their teeth, this find adds the oviraptor to the list of dinosaurs that used these stones as part of their digestion.
The different development levels seen in the fossilized embryos imply that the eggs might not all have hatched at the same time. This is a known occurrence for some birds, but before now, it was thought that this evolutionary development occurred too late for any dinosaur nest to feature it.
The researchers also examined oxygen isotopes in the remains and discovered that the eggs must have been kept at high temperatures typical of the incubation process. This further suggests that the parent was incubating the eggs as a bird does and keeping them at a necessary temperature rather than merely protecting them from an external threat, as a crocodile does.
While finding a dinosaur sitting on some eggs might not be the most exciting example of an activity-depicting fossil there is, the information that scientists can gather from it on the birth, life, and potentially the death of these animals will make this find an important one for years to come.
While other factors exist, sexual prowess appears to have helped determine the role of Protoceratops frills.
- New research seeks to explain why dinosaurs featured an elaborate diversity of ornamentation in their frills and crests.
- A team at the Natural History Museum in London investigated a sheep-size Gobi Desert dweller known as Protoceratops.
- While sex alone does not explain the design, "socio-sexual selection" seems to have played an essential role.
Fewer than 1 percent of all animals that ever lived have been fossilized. Yet fossils are essential for understanding the nature, notes Paige Williams in "The Dinosaur Artist." They provide an evolutionary glimpse into an ancient world. As she writes,
"Without fossils, an understanding of the earth's formation and history would not be possible… We would not know that the climate has warmed and cooled and is changing still… Without fossils, we would not know that birds evolved from dinosaurs; or that Earth was already billions of years old before flowering plants appeared; or that sea creatures transitioned to life on land and primates to creatures that crafted tools, grew crops, and started wars."
Dinosaurs occupy a particularly special place in our collective imagination. Williams states that natural history museums would likely not exist without fossils as well. Now a new study, conducted by researchers at the Natural History Museum in London and published in the journal Proceedings of the Royal Society B, might have answered an age-old question: Why did dinosaurs feature such an elaborate diversity of ornamentation in their frills and crests?
The answer probably won't surprise you, however: sex.
The New Face of Protoceratops?
While there is no way to definitively answer an evolutionary question about Triassic reptiles, postdoctoral researcher Dr. Andrew Knapp has been closely analyzing Protoceratops frills. He was investigating if sexual selection played a role in this sheep-size Gobi Desert dweller.
"In many fossil animals, we have unusual structures and traits which aren't really seen in living animals today. Protoceratops didn't have any horns but they still had a huge frill."
The researchers highlight the importance of "socio-sexual selection" throughout history: traits that serve a variety of purposes, including ornamentation and weaponry, as well as behaviors that helped to establish dominance hierarchies in societies. Humans are not the only species in which the loudest and/or flashiest alphas rise to the top; that information long predates our own genes.
Common examples of sexual selection include the famous tail feathers of peacocks or the elaborate mating rituals of bowerbirds. As Knapp says, however, such rituals are "quite often more complicated than just males being big and flashy and females being dull." He continues,
"While there are quite a few examples in living animals where usually females select males based on the size of their tail feathers or calls, it is quite often overlooked that males do the same thing with females as well."
The case of Protoceratops frills is complex. Knapp and his team made four predictions about the shape of their skulls as possibly playing socio-sexual signaling roles at the outset of their study. Three were supported by the research:
- low integration with the rest of the skull
- significantly higher rate of change in size and shape during ontogeny
- higher morphological variance than other skull regions
The fourth prediction, sexual dimorphism (two different forms existing in the same population), is notoriously difficult to determine given that large sample sizes are needed to understand the impact of each form.
The group looked at 3D scans of 30 Protoceratops skulls and found positive allometry—distinct patterns of growth that could have been sexually selected. Yet without including other factors, such as selecting for coloration of these reptilian ornaments, the team couldn't conclude with certainty that frills were due to mating alone.
Knapp concludes that it's only sex that determined the impact of these frills—but it certainly seems to have played a role.
"The boundaries between sexual and social selection are quite blurred, and social selection will quite often be an important factor too."
Stay in touch with Derek on Twitter and Facebook. His most recent book is "Hero's Dose: The Case For Psychedelics in Ritual and Therapy."
Rocks from two hundred million years ago show us how everything died and how nothing is new.
- A new study suggests that the mass extinction that gave dinosaurs the evolutionary upper hand was caused by oceanic oxygen deprivation.
- Using ratios of sulfur isotopes, researchers could estimate changes in ocean oxygen levels in ancient seas.
- The authors suggest a similar mechanism as that which can cause dead zones in oceans today caused a mass extinction.
Living on Earth isn't always easy. The fossil record is littered with enough mass extinction events to have once made theories that they occur in cycles seem feasible. The "Big Five" events each killed an average of 75 percent of all species alive at the time, with the largest one wiping more than 90 percent of them. While the question of what caused these events is interesting as a curiosity in and of itself, the problem also takes on an existential one, as most people would like to avoid the same fate as the trilobites.
To that end, a team of researchers based out of the UK, China, and Italy have investigated the causes behind one of the most massive die-offs in history. In a new paper published in Science Advances, they suggest a depletion in oxygen as a cause for the event at the end of the Triassic Era 201.3 million years ago.
How to tell what the world was like 201 million years ago using rocks
The mass extinction that ended the Triassic period was a massive die-off that saw somewhere between a quarter and a third of ocean life vanish alongside most large land animals. Plants were not spared a culling either, with perhaps 60 percent of plant species also dying. The event took less than 10,000 years to carry out this morbid work. This remarkable event paved the way for dinosaurs to become the dominant land animal during the Jurassic period, as most of their competition was dead.
Explanations for this event's cause have ranged from gradual climate change, to asteroid impacts, to rampant volcanism. New evidence suggests that ocean anoxia, the depletion of oxygen supplies in the ocean, played a large role.
The researchers examined the levels of two isotopes of sulfur in rocks that would have been on the seafloor during the extinction event from British Columbia, Sicily, and Northern Ireland. The two isotopes, 32S and 34S, can become trapped in limestone and other rocks and exist at different ratios depending on how much oxygen is in the water around them. By examining the changes in the ratio of the two isotopes in rocks formed at the time, we can know what was happening to oxygen levels in the oceans hundreds of millions of years ago.
The scientists noticed "large spikes" in the ratio of 34S to 32S in the samples from all of the locations, indicative of a substantial fall in the amount of oxygen available. These findings can be applied far beyond the sites the rock samples came from, suggesting that oxygen levels fell across large portions of the globe-spanning superocean, known as Panthalassa, that existed alongside Pangea.
And you thought the Dead Zone in the Gulf of Mexico was bad.
This study isn't the only one suggesting Ocean anoxia caused the extinction event. A previous study from 2017 reached a similar conclusion by measuring the trace uranium levels in rocks formed at the time. Similarly to the ratio of sulfur isotopes considered above, the amount of uranium in these rocks varies with the amount of oxygen. That study suggests that the low oxygen levels may have lasted 50,000 years after their initial fall, with a full 250,000 years needed before coral reefs could recover.
In the present day, the researchers hypothesize that this anoxia was connected to significant volcanic activity at the time. By releasing massive amounts of greenhouse gasses, this would have both acidified the oceans by increasing their carbon content and lowered their oxygen levels by raising global temperatures, as warm water holds less oxygen overall. Together, these effects can annihilate marine ecosystems. It is known that major volcanic activity was occurring at the time, lending credence to this hypothesis.
It's a good thing that nothing is causing the oceans to heat up and have lower oxygen levels these days! Oh, wait. Never mind.