Continue reading the main story
It may not be the worst of times, but it is certainly not the best of times. The pandemic has no end in sight. The world is warming, the seas are rising and polar bears are barreling toward extinction. Also: taxes, the 9-to-5 workweek, the renewed threat of nuclear war.
As people looked for someone to blame besides themselves and all of humanity, a culprit emerged in the form of a fish, specifically the 375-million-year-old Tiktaalik (pronounced tic-TAH-lick). Our modern woes would never have existed if our ancestors had never left the water, the reasoning went. Tiktaalik’s four whispers of feet made the fish an easy target.
In 2006, the artist Zina Deretsky made a scientific illustration of Tiktaalik for the National Science Foundation. More recently her depiction of Tiktaalik as a pensive-looking fish poised to leave the water has become the foundation for a flood of memes.
In one, the fish is met with medieval polearms and premonitions: “If you see a Horrid Beast evolving, PUSH IT BACK IN.” The memes yearn to thwack Tiktaalik with a rolled-up newspaper or poke it with a stick — anything to shoo it back into the water and avoid our having to go to work and pay rent.
When Ms. Deretsky first saw one of the memes riffing on her Tiktaalik illustration, she felt she could commiserate. “Our world is a little bit difficult right now,” she said.
Scientists may never know exactly why fish like Tiktaalik and early tetrapods — vertebrates with four limbs — moved onto land, said Alice Clement, an evolutionary biologist and paleontologist at Flinders University in South Australia. “Was it to seek out more food, escape predators in the water, find a safe haven for their developing young?” Dr. Clement asked.
Regardless, their legacy is enormous. The group of fish that moved onto land gave rise to almost half of all vertebrates today, including all amphibians, reptiles, birds, mammals and us. And although we probably cannot trace our family tree directly back to Tiktaalik, “an animal very much like Tiktaalik was a direct ancestor of humans,” said Julia Molnar, an evolutionary biomechanist at the New York Institute of Technology.
If Tiktaalik is our ancestor, then perhaps our holding it accountable for the chaos it sowed is an expression of love.
‘The flop era’
Tiktaalik first became known to humans in 2004, after skulls and other bones of at least 10 specimens turned up in ancient stream beds in the Nunavut Territory of the Arctic. The discoverers, a team of paleontologists including Neil Shubin of the University of Chicago, Ted Daeschler of Drexel University’s Academy of Natural Sciences, and Farish Jenkins of Harvard University, described their findings in two Nature papers in 2006.
A local council of elders known as the Inuit Qaujimajatuqangit Katimajiit were consulted, and they gave Tiktaalik its name, which translates to a large freshwater fish that lives in the shallows, in Inuktitut. The fossils have since been returned to Canada.
Scientists had been searching for a fossil like Tiktaalik, a creature on the cusp of limbs, for decades. And where other fossils required a bit of explanation, Tiktaalik’s obvious anatomy — a fish with (almost) feet — made it the perfect icon of evolution, situated squarely between water and land.
Even then, the fossil fish struck a popular nerve, arriving on the heels of the case of a trial in Pennsylvania that ruled against teaching creationism as an alternative to evolution in high school biology. To Dr. Shubin, society’s collective desire to throw Tiktaalik back into the water is a bit of a relief: You would want to chuck the fish only if you believed in evolution, “which to me is a beautiful thing,” he said.
When Ms. Deretsky illustrated Tiktaalik, she portrayed it with its derrière submerged in water, as the fossil’s back half was a mystery at the time. But in the years since, scientists have amassed more than 20 specimens and seen more of its anatomy, including its pelvis, hind fin and the joints of its skull.
In particular, computed tomography scans taken by Justin Lemberg, a researcher in Dr. Shubin’s lab, have allowed scientists to peer inside rock to see the bones within. The scans spawned 3-D models of Tiktaalik’s unseen parts. Some scans revealed that Tiktaalik had unexpectedly massive hips (more like Thicctaalik) and a surprisingly big pelvic fin. The fish, instead of dragging itself with only its fore-fins, like a wheelbarrow, appeared to use all four fins to get around, like a jeep.
Other scans revealed the delicate bones of its pectoral fin. Unlike the symmetrical rays of fish fins, Tiktaalik’s fin bones were noticeably asymmetrical, which allowed the joints to bend in one direction. “We think that was because these animals were interacting with the ground,” said Thomas Stewart, an incoming evolutionary and developmental biologist at Penn State University.
Tiktaalik’s fins hold special allure for researchers investigating the genetic underpinnings of our own hands. Tetsuya Nakamura, an evolutionary developmental biologist at Rutgers University who hopes to genetically manipulate a zebrafish into growing fingers, hung illustrations of Tiktaalik’s fin in his lab like a beacon: “The ideal image we want to create in our lab,” Dr. Nakamura said.
Tiktaalik’s existence was ideal in other ways. The fish trundled around in the Late Devonian, an enviously halcyon version of Earth in which the climate was pleasant and mild and the seas were full of fish. Tiktaalik may have spent its days cruising around stream banks and swamps teeming with plants, Dr. Daeschler said.
That era on Earth was a goofy time to be a vertebrate, according to Ben Otoo, a graduate student studying early tetrapods at the University of Chicago. The vertebrates that did venture on land were still getting their land legs. “It’s a lot of galumphing, wriggling, slithering, huffing, flopping,” they said. “It’s literally the flop era.”
Although the Late Devonian was a dangerous time to be prey, it was also a place of mental peace — a time before self-awareness and embarrassment. “Everyone is, like, only barely conscious of the idea that they’re alive,” Mr. Otoo said. “It’s great, just vibes.”
And Tiktaalik’s flat head, with two eyes resting on top like blueberries on a pancake, made it perfectly suited for gazing above the water. “It looks like a muppet,” said Yara Haridy, an incoming researcher at the University of Chicago. “It’s very muppety.”
Other land-curious fish or early tetrapods were no less ridiculous-looking. Before Tiktaalik, flat-skulled Panderichthys swam in the shallows. Later, Acanthostega boasted a recognizable but underwhelming suite of limbs. And Elpistostege, a fish quite similar to Tiktaalik, also blurred the line between fin and hand.
So if modern humans want to blame Tiktaalik for our woes, it seems only fair that we blame all the other nascent land-dwellers — those known and those yet to be discovered — for ushering in self-awareness and W-2 forms.
The fish that launched 1,000 memes
All the known fossilized Tiktaaliks represent adult fish, so researchers hope to discover other earlier stages that could illuminate its life history, such as whether it undergoes metamorphosis.
“It would be really fun to find a bunch of babies,” said Dr. Daeschler, who will scour the Canadian Arctic again this summer. He noted that true babies would probably not ossify into fossils, as their bones are too small. But a juvenile Tiktaalik, about as long as a burpless cucumber, might have survived. And who could blame a baby for anything?
To be fair, even the adult Tiktaalik could not have predicted any of this; it had no grand plan to colonize on land. “It’s not like, ‘Oh, because limbs are better,’” Dr. Daeschler said. “Or the animals saw things on land and thought, ‘Oh, I need to evolve.’”
It is also a stretch to say the aquatic fish walked on land at all in any meaningful way. Rather, Dr. Daeschler suggested, Tiktaalik was exploiting new ecological opportunities at the water’s edge, scooting through the shallows where limbless fish could not tread.
And would-be Tiktaalik-bashers should be aware that a mere stick may not have been enough to deter an adult. Although reconstructions of its face appear “innocent and dopey,” said Dr. Stewart of Penn State University, the fish was as large as a person. “It changes the way you think about it, from kind of a little fishy thing to a more imposing animal in the water,” Dr. Stewart said.
Art need not mirror reality to convey a truth. Tiktaalik memes do not merely offer up a scapegoat for modern malaise. They also ask us to imagine a different past, present and future. What would happen if we could rechart the course of evolutionary history?
“It’s a really powerful thought, and I don’t believe there is anything inevitable about the path that evolution has taken,” Dr. Molnar said of the memes. “If you wound back the clock, you’d wind up in a completely different place,” she added, paraphrasing the biologist Stephen Jay Gould.
So if Tiktaalik signifies regret, it also signifies radical possibility. For Mr. Otoo, the fossil conjures a utopian optimism, a reminder that Earth has had many former selves and will have many more.
“The natural world we tend to think of as being very immutable and static — you look at things and say, ‘Oh, that’s how things are,’” they said. But 300 million years ago the continents were all glued together into one. Even Earth can be reshaped with time.
And if Earth can change, so too can humans, Mr. Otoo reasons. “Through various combinations of conscious and unconscious decisions, we made the created world this way,” they said. “And we can make it differently.”
Besides, who is to say that the descendants of a Tiktaalik that never left the water would not have created its own unbearable underwater world, where polymetallic nodules are harvested by unpaid octopuses and hermit crabs must pay rent on their shells? Greed can exist below the surface, too.
Abhor the message, not the messenger, Mr. Otoo advises. “You don’t hate Tiktaalik,” they said, adding: “You hate capitalism.”
Continue reading the main story
The fossilised remains of an ancient beast have revealed how prehistoric life hauled itself from the water and took its first unsteady steps along the path that led to four-legged land animals.How did the Tiktaalik go extinct? ›
There is not enough information on what caused the extinction of Tiktaalik. The end of the Late Devonian era is considered one of earth's mass extinction events. Tiktaalik lived during the start of the Late Devonian period. Thus, it probably died out after the extinction event that ended the Devonian period.Did we evolve from Tiktaalik? ›
The Human Edge: Finding Our Inner Fish One very important human ancestor was an ancient fish. Though it lived 375 million years ago, this fish called Tiktaalik had shoulders, elbows, legs, wrists, a neck and many other basic parts that eventually became part of us.Where did the fish evolve from? ›
Fish may have evolved from an animal similar to a coral-like sea squirt (a tunicate), whose larvae resemble early fish in important ways. The first ancestors of fish may have kept the larval form into adulthood (as some sea squirts do today), although this path cannot be proven.How did humans evolve from fish? ›
The conventional understanding has been that certain fish shimmied landwards roughly 370 million years ago as primitive, lizard-like animals known as tetrapods. According to this understanding, our fish ancestors came out from water to land by converting their fins to limbs and breathing under water to air-breathing.Did we evolve from fish or monkeys? ›
Like modern-day apes and monkeys, we evolved from ancient monkeys. And like all vertebrates with four-limbs, known as tetrapods, we evolved from the same ancient fishes.Are Tiktaalik fish still alive? ›
Tiktaalik roseae, an extinct fishlike aquatic animal that lived about 380–385 million years ago (during the earliest late Devonian Period) and was a very close relative of the direct ancestors of tetrapods (four-legged land vertebrates).What is a fish with legs called? ›
This is definitely the case with the axolotl, which is often referred to as the "Mexican walking fish." First, this little guy is not a fish; rather, he's a neotenic salamander (a kind of amphibian). Neotenic salamanders are generally characterized by a lizard-like appearance, with thin bodies and somewhat stumpy legs.What was the first creature to walk on land? ›
More than 420 million years ago ancient millipedes took their first many—many, many, many—steps onto land.Is human still evolving? ›
What is clear however, is that all organisms are dynamic and will continue to adapt to their unique environments to continue being successful. In short, we are still evolving.
More reproduction followed, and more mistakes, the process repeating over billions of generations. Finally, Homo sapiens appeared. But we aren't the end of that story. Evolution won't stop with us, and we might even be evolving faster than ever.Who was the first human on Earth? ›
Homo sapiens, the first modern humans, evolved from their early hominid predecessors between 200,000 and 300,000 years ago. They developed a capacity for language about 50,000 years ago. The first modern humans began moving outside of Africa starting about 70,000-100,000 years ago.Did all humans start as a fish? ›
The way this happens only really makes sense when you realise that, strange though it may sound, we are actually descended from fish. The early human embryo looks very similar to the embryo of any other mammal, bird or amphibian - all of which have evolved from fish.When did fish start to evolve? ›
The first fish appeared around 530 million years ago and then underwent a long period of evolution so that, today, they are by far the most diverse group of vertebrates.What was the first fish to evolve? ›
530 million years ago: The Pikaia species, the first known fish on Earth, evolved in the middle of the Ordovician period. Around 530 million years ago: Haikouichthys, the earliest fish species discovered, evolved as one of the earliest vertebrate organisms in the world. It has a notochord and multiple gills.How did life start on earth? ›
Many scientists believe that RNA, or something similar to RNA, was the first molecule on Earth to self-replicate and begin the process of evolution that led to more advanced forms of life, including human beings.Why is it called a human fish? ›
Origin of the name human fish
Proteus or the olm, has gotten its nickname “human fish” due to its fleshy skin color. His skin has zero protective pigmentation in its skin. However, if exposed to light the skin will begin to darken.
One pretty wild contribution to these hypotheses was by an ancient Greek philosopher Anaximander. He held the belief that humans actually evolved from fish (no, you didn't read that wrong).How was the first human created? ›
Human evolution is the lengthy process of change by which people originated from apelike ancestors. Scientific evidence shows that the physical and behavioral traits shared by all people originated from apelike ancestors and evolved over a period of approximately six million years.How did humans get on earth? ›
The first human ancestors appeared between five million and seven million years ago, probably when some apelike creatures in Africa began to walk habitually on two legs. They were flaking crude stone tools by 2.5 million years ago. Then some of them spread from Africa into Asia and Europe after two million years ago.
Firstly, humans did not evolve from monkeys. Instead, monkeys and humans share a common ancestor from which both evolved around 25 million years ago. This evolutionary relationship is supported both by the fossil record and DNA analysis. A 2007 study showed that humans and rhesus monkeys share about 93% of their DNA.Can any fish walk? ›
Though more than 100 species of hillstream loach are found throughout Southeast Asia, the cave angel fish is the only one whose walking capabilities have been observed.What kind of fish are humans? ›
Humans are jawed vertebrates. The ancestors of jawed vertebrates were similar to that of eyeless, jawless and boneless fishes such as lampreys and hagfishes. They diverged from their immediate ancestor some 300 million years ago.Is Tiktaalik a dinosaur? ›
Tiktaalik (/tɪkˈtɑːlɪk/; Inuktitut ᑎᒃᑖᓕᒃ [tiktaːlik]) is a monospecific genus of extinct sarcopterygian (lobe-finned fish) from the Late Devonian Period, about 375 Mya (million years ago), having many features akin to those of tetrapods (four-legged animals).Are there more eyes or legs? ›
There was big debate across the internet over the question “are there more doors or wheels in the world?” But Dan and Leon wanted to discuss if there are more eyes or legs in the world. Every human on earth has two eyes and two legs. But some animals have no legs like snakes or fish.Do fish have 6 legs? ›
So the mean number of legs for land vertebrates is very close to 4 (it's actually about 3.96). Fish don't have any legs of course, and there are another ten trillion of those, so including them brings the average back down to 2. But this is only for vertebrates.Which fish can walk? ›
Snakehead fish have evolved to “walk” on land! They propel themselves forward by moving their head and back fin in opposite directions. Underwater, a snakehead absorbs oxygen through its gills, just like other fish.Where was the first human born? ›
The first humans emerged in Africa around two million years ago, long before the modern humans known as Homo sapiens appeared on the same continent. There's a lot anthropologists still don't know about how different groups of humans interacted and mated with each other over this long stretch of prehistory.What was the first creature with legs? ›
The first tetrapods probably evolved in the Emsian stage of the Early Devonian from Tetrapodomorph fish living in shallow water environments. The very earliest tetrapods would have been animals similar to Acanthostega, with legs and lungs as well as gills, but still primarily aquatic and unsuited to life on land.What was here before dinosaurs? ›
Plant life consisted mostly of ferns, conifers and small shrubs. Animals included sharks, bony fish, arthropods, amphibians, reptiles and synapsids. The first true mammals would not appear until the next geological period, the Triassic.
Worldwide there are roughly two new mutations for every one of the 3.5 billion base pairs in the human genome every year, says Hodgson. Which is pretty amazing - and makes it unlikely we will look the same in a million years.Are humans monkeys? ›
Humans and monkeys are both primates. But humans are not descended from monkeys or any other primate living today. We do share a common ape ancestor with chimpanzees. It lived between 8 and 6 million years ago.Are humans evolving shorter? ›
We are now generally shorter, lighter and smaller boned than our ancestors were 100,000 years ago. The decrease has been gradual but has been most noticeable in the last 10,000 years. However, there has been some slight reversal to this trend in the last few centuries as the average height has started to increase.How long do humans have left? ›
Humanity has a 95% probability of being extinct in 7,800,000 years, according to J.Are humans becoming weaker? ›
While there is no proof that modern humans have become physically weaker than past generations of humans, inferences from such things as bone robusticity and long bone cortical thickness can be made as a representation of physical strength.
The skull will get bigger but the brain will get smaller
Humans in the year 3000 will have a larger skull but, at the same time, a very small brain. "It's possible that we will develop thicker skulls, but if a scientific theory is to be believed, technology can also change the size of our brains," they write.
ADAM1 was the first man. There are two stories of his creation. The first tells that God created man in his image, male and female together (Genesis 1: 27), and Adam is not named in this version.What color was the first human? ›
From about 1.2 million years ago to less than 100,000 years ago, archaic humans, including archaic Homo sapiens, were dark-skinned.Why do humans have 2 legs? ›
Scientists claim that walking on two legs was one of the keys to humans' development from ancient ape-like ancestors. Walking on two legs saved energy and allowed the arms to be used for activities like hunting, crafting simple tools and interacting with objects.What animal did humans evolve from? ›
Abstract. Humans diverged from apes (chimpanzees, specifically) toward the end of the Miocene ~9.3 million to 6.5 million years ago. Understanding the origins of the human lineage (hominins) requires reconstructing the morphology, behavior, and environment of the chimpanzee-human last common ancestor.
Humankind evolved from a bag-like sea creature that had a large mouth, apparently had no anus and moved by wriggling, scientists have said. The microscopic species is the earliest known prehistoric ancestor of humanity and lived 540 million years ago, a study published in the journal Nature said.How are fish and humans similar? ›
Homologous features shared by human and fish lighten up the evolutionary pathway from the earliest vertebrate by sharing similar structures of the hands and fins. The development of teeth that diversified into features that showed up from the skin, and down to the instruction that made us who we are.Why did fish evolve into land animals? ›
Those fish that had the flexibility to allow them to move out onto land were able to remove themselves from a very competitive environment and into a new habitat of plants and insects. This new habitat proved advantageous, rewarding them with increased shelter and food resources.What did the first fish look like? ›
The oldest fossils of animals resembling a fish date back between 518 million and 530 million years ago. Discovered in China and called Haikouichthys, these animals were about an inch long (2.5 cm) and had a head with seven to eight slits at its base that looked like gills.Are fish still evolving? ›
There are fish on our planet right now that are evolving to live on land, and a new study shows they are spurred on by predators in the water. It's a pretty big deal for a little fish - moving from the familiar waters of the ocean to the dry and rocky shoreline.What was the first animal? ›
The First Animals
Sponges were among the earliest animals. While chemical compounds from sponges are preserved in rocks as old as 700 million years, molecular evidence points to sponges developing even earlier.
The first amphibians evolved from a lobe-finned fish ancestor about 365 million years ago. They were the first vertebrates to live on land, but they had to return to water to reproduce. This meant they had to live near bodies of water.What did the first fish Think answer? ›
The first fish lineages belong to the Agnatha, or jawless fish. ans2) He believed that whatever was to happen would happen and nobody could change it.What animals evolved from Tiktaalik? ›
Those fins and other mixed characteristics mark Tiktaalik as a crucial transition fossil, a link in evolution from swimming fish to four-legged vertebrates. This and similar animals might be the common ancestors of all vertebrate terrestrial fauna: amphibians, reptiles, birds, and mammals.Which has Tiktaalik as an ancestor? ›
Tiktaalik, or a fish like it, is our ancestor – but not just ours, that of all tetrapods: kangaroos, woolly mammoths, and even snakes and velociraptors.
Researchers have discovered well-preserved pelves and a partial pelvic fin from Tiktaalik roseae, a 375 million-year-old transitional species between fish and the first legged animals, which reveal that the evolution of hind legs actually began as enhanced hind fins.Is Tiktaalik the ancestor of tetrapods? ›
Tiktaalik represents a close relative of the ancestor of tetrapods, and its fossils date to 375 million years ago. The first unambiguous fossils of tetrapod bones (e.g. Acanthostega) date to just after that time.Do Tiktaalik still exist? ›
Tiktaalik roseae, an extinct fishlike aquatic animal that lived about 380–385 million years ago (during the earliest late Devonian Period) and was a very close relative of the direct ancestors of tetrapods (four-legged land vertebrates).Did dinosaurs come from fish? ›
As reviewed in a new paper in the Annual Review of Ecology, Evolution, and Systematics, about 398 million years ago there was a particular group of fish, the lobed-fined or sarcopterygian fish, the organisms that gave rise to our common ancestor with the dinosaurs.What was the first land animal on earth? ›
Millipedes: The First Land Animals.Who was the first human on earth? ›
Homo sapiens, the first modern humans, evolved from their early hominid predecessors between 200,000 and 300,000 years ago. They developed a capacity for language about 50,000 years ago. The first modern humans began moving outside of Africa starting about 70,000-100,000 years ago.How do you the explain the changes in populations of organisms through time? ›
Evolution is a process that results in changes in the genetic material of a population over time. Evolution reflects the adaptations of organisms to their changing environments and can result in altered genes, novel traits, and new species.Which factors affect natural selection? ›
Natural selection occurs only if there is both (1) variation in the genetic information between organisms in a population and (2) variation in the expression of that genetic information—that is, trait variation—that leads to differences in performance among individuals.Is the study of the geographic distribution of modern and extinct species? ›
Biogeography, the study of the geographical distribution of organisms, provides information about how and when species may have evolved. Fossils provide evidence of long-term evolutionary changes, documenting the past existence of species that are now extinct.Is Archaeopteryx a bird or dinosaur? ›
Archaeopteryx is considered by many to be the first bird, being of about 150 million years of age. It is actually intermediate between the birds that we see flying around in our backyards and the predatory dinosaurs like Deinonychus.
Although fish lack a true, anatomical neck, studies of their feeding suggest the backbone could function as a neck by bending upwards to lift the head away from the body. If fish do have a hidden "neck", it is powered by the body muscles, which extend from head to tail in a complex architecture of muscle fibres.