Discovery of Hagfish Eyes Debunks Claim About Eye Evolution

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The discovery of sophisticated eyes in a fossilized hagfish has dethroned the modern blind hagfish as the only observable so-called intermediate form in eye evolution.

  • Hagfish are blind because their eyes are missing many essential parts.
  • Evolutionists have long seen hagfish as a living transitional form in the story of eye evolution.
  • Discovery of complex eyes in an ancient hagfish fossil robs evolutionists of their supposed intermediate form.
  • Hagfish originally had good eyes and lost them, but this is not reverse evolution because eye complexity did not evolve in the first place.
  • Hagfish with complex eyes were designed by a wise Creator God, but they have degenerated like so many other things in this sin-cursed world.

What can a creature’s eyes tell us? How about where it ranks on the evolutionary scale? Until recently the hagfish was seen as a living example of an intermediate form in the stepwise evolution of eyes. Its blind eyes1 with sightless retinas lack image-forming essentials like a lens, iris, and melanin2 pigment3 as well as muscles for eye movement. The eyes can even be buried beneath its skin!4 The hagfish was therefore thought to have less evolved eyes than its creepy cousin the lamprey,5 which has a sophisticated camera-type eye. Together these jawless fish were thought to speak volumes about the evolutionary history of the vertebrate eye.

So Many Camera-Type Eyes and Not an Evolutionarily Primitive One in the Bunch

A camera-type eye collects and focuses light to form an image on a light-sensitive surface, the retina. We have them. So do lampreys and the overwhelming majority of animal species. Appearing in a wide variety of configurations, the complex camera-type eye is seen in all sorts of vertebrates as well as mollusks and arthropods. Complex eyes are seen in such a wide variety of fossils from the Cambrian explosion on up that evolutionists believe evolution produced camera-type eyes independently 50 to 100 times.

The evolutionary story of “how we got our eyes” is muddled by a disturbing lack of transitional forms, either in the fossil record or among living animals. The hagfish was really the evolutionary storyteller’s only hope. The hagfish’s lack of so many essential eye parts has been considered significant to understanding how vertebrate6 eyes evolved because it seemed to represent a transitional form—“a rudimentary intermediate evolutionary grade in the gradual assembly of the vertebrate eye.”7

Now in light of new discoveries in the fossil record, evolutionists must abandon the hagfish as the last living candidate for an intermediate, evolutionary form of eyes. Why? Because careful study of fossilized hagfish reveals hagfish once had nicely developed eyes! Evolutionists must regroup and imagine that hagfish and lampreys shared an even more ancient eyeless ancestor for which there is no living or fossil evidence at all. Thanks to the vision of ancient hagfish, what evolutionists once thought they could demonstrate using hagfish blindness has changed in the proverbial blink of an eye.


The hagfish is a jawless fish. Modern hagfish are blind, and their eyes are missing so many parts that they hardly qualify as eyes. But ancient hagfish, scientists recently learned, had complex eyes like a lamprey’s. This discovery means that hagfish can no longer be used as an example of an intermediate evolutionary step in eye evolution. Image by Pbsouthwood, via Wikimedia Commons.

State of the Evidence for Eye Evolution

Evolutionists hold that eyes have evolved convergently many times. How else can they explain the existence of complex camera eyes in such distinctly different creatures as the invertebrate octopus and vertebrate orangutan? But in trying to trace the evolutionary lines even within a more limited group like vertebrates, the fossil record—replete with complex eyes in many sorts of animals—has offered no support to their claims. As the discoverers of the extinct hagfish’s eyes write, “In the absence of useful data from fossils, scenarios for evolutionary assembly of the vertebrate eye have been based necessarily on evidence from development, molecular genetics and comparative anatomy in living vertebrates.”8

In other words, without a series of simple-eyed fossils showing the apparent steps in eye evolution, evolutionists have had to look to living animals for support. They assume, for instance, that observable embryonic organ development retraces, or recapitulates, evolutionary stages. They also believe that the comparative anatomy and genetics of modern animals offer clues revealing how eye evolution happened. (As we’ve often discussed, such observable biology in the present only reveals how things are, not how they supposedly evolved unobserved over millions of years. The evidence only demonstrates evolutionary changes if viewed through evolutionary glasses. See “Do Naked Bearded Dragons Reveal Common Ancestry of Scales, Feathers, and Fur?” for a recent example of this.)

Sea Lamprey

Lampreys, like hagfish, are jawless, cartilaginous fish. Despite their eel-like look, they are not eels. (Eels have bones and jaws.) Unlike the hagfish, the lamprey, like humans and the majority of animal species, has a complex camera-type eye. Image by Nicke L, via Wikimedia Commons.

The Iconic Place of the Hagfish in Eye Evolution

Even among supposed evolutionary evidences from the living, only the team of hagfish and lamprey have provided any useful examples. Sarah Gabbott, geology professor at the University of Leicester and lead author of the study reporting the landmark discovery of genuine complex eyes in a hagfish, explains, “To date models of vertebrate eye evolution focus only on living animals and the blind and ‘rudimentary’ hagfish eye was held-up as critical evidence of an intermediate stage in eye evolution. Living hagfish eyes appeared to sit between the simple light sensitive eye ‘spots’ of non-vertebrates and the sophisticated camera-style eyes of lampreys and most other vertebrates.”9

Because it is so deficient in necessary parts, “It has been postulated that the hagfish eye reflects a failure in eye development to proceed beyond that of an earlier stage in vertebrate eye evolution,” Gabbott’s team writes.10 They recall the commonly accepted contribution of the hagfish to evolutionary understanding:

The condition of hagfish eyes has proved particularly influential in scenarios of eye evolution. In contrast to lampreys, which possess a sophisticated eye with a lens, iris and eye muscles, hagfish eyes lack such structures and, unlike almost all other vertebrates, including lampreys, the retinal epithelium of hagfish is devoid of pigment granules. This condition has been interpreted to reflect a rudimentary intermediate evolutionary grade in the gradual assembly of the vertebrate eye.11

Until now, that is. This new evidence from the fossil record has, in reality, set back evolutionary claims even further, for the ancient hagfish’s eyes are anything but primitively simple structures.

Scans See What No One Suspected

Gabbott and her colleagues used scanning electron microscopy to take a closer look at nine fossil lampreys, Mayomyzon pieckoensis, and the only known fossilized hagfish, Myxinikela siroka. These museum specimens came from the Mazon Creek Lagerstätte, Late-Carboniferous shale believed by evolutionists to be 307 million years old. They confirmed that the pair of dark dots in the place where eyes should be really are eyes, even on the hagfish. Key anatomical landmarks match those on modern lamprey eyes, with the dark round inner ear, located behind the eyes, even being preserved on some of the lamprey specimens.12 And even though modern hagfish do not exhibit eye complexity, the details in the dark dots on the fossilized hagfish match those in the fossil lampreys’ complex eyes.

Additional tests using ion mass spectrometry confirm that the dots are dark because they contain pigmented granules—melanosomes—full of the retinal pigment melanin. It is indeed remarkable that these fragile structures and the delicate molecules they contain have been preserved so nicely in the fossil record—the “surprising durability of melanosomes and biomolecular melanin”13 being a testament to the rapid catastrophic burial that froze them in time nearly 4,400 years ago during the global Flood. Could these melanosomes be something else, like fossilized microbes, for instance? The researchers answer that question with a resounding “no.” These melanosomes are confined to the eyes and to other known pigmented regions of the body, like stripes on the skin.14

Hagfish, the study demonstrates, once had eyes resembling the complex eyes of the lamprey. The researchers write, “Myxinikela is a hagfish, and the recognition of pigmented eyes in this taxon indicates that the eyes of extant hagfish are degenerate, not primitively simple.”15 Furthermore, they write, “Our data indicate that the eyes of extant hagfishes are degenerate and are not an appropriate model for the evolutionary assembly of the vertebrate eye.”16

So what happened to the hagfish’s eyes? Like blind cave fish, the modern hagfish has either lost the information for producing eyes or stopped expressing that information. Is that evolution or “devolution” or reverse evolution? Not at all. No one has shown that the information to make eyes in the first place was acquired through random natural processes, so the process of evolution has not been reversed. Neither is the loss of information or the end of its expression the same as acquiring new information.

Have Evolutionists Conceded on Eye Evolution?

Based on the evidence from the hagfish fossil, there was nothing primitively simple about the ancient hagfish eye. Fossil evidence indicates the ancient hagfish eye was not a transitional form. Having lost their only supposed intermediate form of the vertebrate eye, have evolutionists given up their model? Of course not. They still assume that the vertebrate eye evolved through a series of steps but presume that the fossil evidence for this bit of visual history remains undiscovered, deeper in history and perhaps lost to the ravages of time and chance.

Fossil evidence indicates the ancient hagfish eye was not a transitional form.

Creationists have long pointed out the lack of fossil evidence for eye evolution. Gabbott admits as much, saying, “Sight is perhaps our most cherished sense but its evolution in vertebrates is enigmatic and a cause célèbre for creationists.”17 And even though she claims, “We bring new fossil evidence to bear on an iconic evolutionary problem: the early evolution of the vertebrate eye,”18 her discovery adds nothing to the evolutionary story, demonstrating only that the commonly held evolutionary story of the eye is without merit.

But Gabbott seems confident that the ability to see the eyes of creatures that presumably lived millions of years ago with modern imaging technology only means that the answers to the evolutionary story of the eye are just around the corner. She says, “We will now scrutinize the eyes of other ancient vertebrate fossils to see if we can finally build a picture of the sequence of events that took place in early vertebrate eye evolution.”19

Seeing Evolutionary Lines Connecting the Dots

Why, some might ask, do evolutionists hang onto their story when the evidence does not support it? Well, it comes down to worldview. No scientist was around to observe the origin of eyes. And even if the fossil record contained a series of extinct vertebrate eyes that could be arranged from primitive to complex—and evolutionists concede it does not—those would represent only a collection of animals with different sorts of eyes. Only the evolutionary imagination—the belief that the existence of complex eyes means they must have evolved through a series of natural processes—connects the dots between such fossils.

If a person already assumes the only acceptable explanation is an evolutionary one, then he or she is predisposed to fill in unobservable details about origins with unverifiable evolutionary processes. If a person understands that the only eyewitness to the origin of eyes is the Creator God of the Bible, then he or she is able to see that the observable evidence relevant to this visual history fits the biblical account perfectly.

According to Genesis, during the last few days of the creation week about 6,000 years ago, God created all the animal kinds as well as the first two people, fully formed and functional without any time for evolution’s natural processes. The kinds of fish God created on the fifth day of that week (Genesis 1:20–23) were designed to reproduce after their kinds. Biological observations affirm that animals (and humans) only reproduce and vary within their created kinds, being unable to acquire the information to evolve into new more complex kinds of creatures through natural processes.

Degeneration and Death Invaded God’s Perfect World

Once a person understands that the most reliable source of information about our distant past is the Word of the all-knowing God who created us and saw it all unfold, the existence of the blind hagfish makes sense.

The loss of genetic information, or the cessation of its expression as is seen in blind cavefish (see “How Cavefish Went Blind, and Why It Matters”), is not evolution but only the sort of loss that occurs in a world fraught with deterioration and degeneration since man’s sin introduced death into the perfect world God made. Once a person understands that the most reliable source of information about our distant past is the Word of the all-knowing God who created us and saw it all unfold, the existence of the blind hagfish makes sense.

Originally created with eyes that could see, this particular animal today still gets along fine in its degenerate condition. It has four pairs of sensory tentacles that serve well despite its lack of vision. The blind hagfish tunnels beneath the gills and into the various other openings on carcasses and consumes them from the inside out, even absorbing some nutrients directly through its skin.20 Though many are eaten by other fish, the hagfish is equipped to protect itself. It generates such copious amounts of slime that it can make a potential predator lurch in a gagging-like way to clear its gills.21 Yet it can tie itself in a knot to scrape this gill-clogging material away from its own face. (Watch hagfish slime would-be predators for yourself in the short video “Hagfish Slime Defence Mechanism” on YouTube.) These strands of slime—each 15 cm long—are an engineering marvel, being manufactured, coiled, and stored within cells for instant deployment when needed.22 The abundant slime is even harvested for an egg-white-like use in Korean cuisine.23

The rather grisly behavior of the hagfish indicates it could be the poster child not for eye evolution but for the sorts of predatory behaviors that have developed in our sin-cursed world. In addition to scavenging in ways we may find repugnant,24 hagfish are also predatory. They have even been observed purposefully suffocating gill-breathing fish with their slime and carrying them off for a private feast.25 Thus when we look at the modern hagfish not staring back at us, we should not see evidence of evolution as Gabbott suggests (despite her discovery to the contrary), but we should see an example of a well-designed animal that has degenerated since God created it about 6,000 years ago, joining in the world of death that has reigned since Adam’s rebellion against our Creator.

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  1. Some living hagfish have light-detecting, pigmented eyespots, but they do not have the equipment to resolve images.
  2. Melanin pigment serves important functions in sighted eyes, including the capture of light and, as an antioxidant, protection of delicate tissues from toxic by-products of the retina’s high metabolic rate.
  3. Living hagfish actually do have some retinal pigment, but not melanin. Both hagfish and lampreys have melanopsin in their retinal epithelium. Melanopsin serves only non-image-forming light-detecting roles in people, but it is thought to serve image-forming functions in some animals, possibly including the lamprey, which does have complex functional eyes. Melanopsin is encoded by only a single gene in both the hagfish and the lamprey, but that gene is expressed differently. Hagfish melanopsin is primarily found in only one sort of cell in the hagfish retina but in two sorts of retinal cells in the lamprey. Because the modern hagfish’s eye is not equipped to focus an image on its retina, its melanopsin can now serve it only as a light-dark detector. From Lanfang Sun et al., “Distribution of Mammalian-Like Melanopsin in Cyclostome Retinas Exhibiting a Different Extent of Visual Functions,” PLOS One 9, no. 9 (2014): doi:10.1371/journal.pone.0108209.
  4. Ibid., 2.
  5. Sarah Gabbott et al., “Pigmented Anatomy in Carboniferous Cyclostomes and the Evolution of the Vertebrate Eye,” Proceedings of the Royal Society B 283, no. 1836 (2016): 1, doi:10.1098/rspb.2016.1151.
  6. The lamprey, like the hagfish, is a jawless, cartilaginous fish. The lamprey has cartilaginous vertebrae. The hagfish does not; but because it has vertebrae-like structures as an embryo, as well as a cartilaginous skull as an adult, it is generally considered a vertebrate. (See Kinya Ota et al., “Identification of Vertebra-Like Elements and Their Possible Differentiation from Sclerotomes in the Hagfish,” Nature Communications 2, no. 373 [2011]: doi:10.1038/ncomms1355.)
  7. Gabbott et al., “Pigmented Anatomy in Carboniferous Cyclostomes and the Evolution of the Vertebrate Eye,” 1.
  8. Ibid.
  9. University of Leicester, “New Light Shed on How Vertebrates See: Details in Eyes of 300-Million-Year-Old Lamprey and Hagfish Fossils,” Science Daily, August 2, 2016,
  10. Gabbott et al., “Pigmented Anatomy in Carboniferous Cyclostomes and the Evolution of the Vertebrate Eye,” 6.
  11. Ibid., 1.
  12. These optic capsules are seen just behind the dark pairs of eyes in three of the fossil lamprey specimens. (Ibid., 2)
  13. Ibid.
  14. They also do not match up with what is known about the size, shape, and variability of fossilized bacteria. (Ibid., 3)
  15. Ibid., 6.
  16. Ibid.
  17. University of Leicester, “New Light Shed on How Vertebrates See: Details in Eyes of 300-Million-Year-Old Lamprey and Hagfish Fossils.”
  18. Ibid.
  19. Ibid.
  20. Hannah Waters, “14 Fun Facts About Hagfish,” Smithsonian, October 17, 2012,
  21. Vincent Zintzen et al., “Hagfish Predatory Behavior and Slime Defence Mechanism,” Scientific Reports 1, no. 131 (2011): doi:10.1038/srep00131.
  22. As discussed by hagfish expert Dr. Douglas Fudge, associate professor of integrative biology, University of Guelph, in “Fun with Silly String & Hagfish” at
  23. John Bocskay, “The Good, the Bad, and the Hagfish,” Sweet Pickles and Corn,
  24. Waters, “14 Fun Facts About Hagfish.”
  25. Zintzen et al., “Hagfish Predatory Behavior and Slime Defence Mechanism.”


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