The Betta Bowl and the Wild Horse: Where UsefulCharts Gets Biology Wrong
Matt Baker has a gift for turning the bewildering history of life on Earth into something people can understand. His UsefulCharts project transforms millions of years of evolution into colourful family trees, connecting familiar animals to ancestors most of us have never heard of.
But in Family Tree of Fish, Amphibians & Reptiles, the simplicity becomes a liability.
Baker tells viewers that betta fish can live in tiny bowls, dismisses wild horses as domesticated animals gone feral, and identifies a tortoise as the oldest living vertebrate. Elsewhere, he blurs the distinction between evolutionary relationships and the biological characteristics of individual species.
These are not merely arguments about obscure scientific names. One concerns how people care for living animals. Another erases an endangered species from its proper evolutionary context.
And there is a troubling contradiction at the heart of the project: Baker is selling scientific classification charts while acknowledging that his knowledge of some of the animals he is classifying is limited.
His willingness to accept corrections is welcome. But scientific accuracy cannot depend entirely on whether the right expert happens to leave a YouTube comment.
The Betta Fish: Surviving in a Bowl Is Not Living Well
The most consequential mistake comes during Baker's discussion of aquarium fish.
He tells viewers that Siamese fighting fish, commonly called bettas, can live in very small spaces because their natural habitats include ponds.
He then explains that this is why they are frequently sold in small bowls.
It sounds like a harmless observation about an unusually adaptable animal. It is also precisely the misconception that animal-welfare researchers have been trying to correct.
In January 2024, researchers Ronald Oldfield and Emily Murphy published a study in Animal Welfare examining how aquarium size and environmental enrichment affected Siamese fighting fish.
They tested male bettas in containers ranging from tiny 0.5-litre bowls to aquariums holding 208 litres.
The results were revealing.
Fish confined to the smallest bowls spent significantly less time swimming than those housed in larger aquariums. Providing environmental enrichment, including plants and other structures, also encouraged swimming.
The researchers concluded that an aquarium of at least 10 litres was needed to allow the fish to express normal swimming behaviour.
That is a substantial difference from the tiny decorative bowls commonly marketed to consumers.
The RSPCA's guidance goes further. It recommends tanks of 20 litres or more, with 10 litres as an absolute minimum.
It also advises owners to maintain water temperatures between 24°C and 26°C, provide appropriate filtration, and offer plants or other forms of shelter. Small bowls often cannot accommodate adequate heating or provide sufficient space.
Baker's explanation confuses an animal's capacity to survive difficult environmental conditions with evidence that those conditions are suitable for its welfare.
A fish capable of surviving in shallow, oxygen-poor water has not thereby evolved a preference for a cramped glass container.
The distinction matters because viewers may act on what they learn. A parent watching the video might reasonably conclude that a small bowl is an acceptable home for a child's first fish.
Baker does not explicitly recommend neglecting bettas. But he provides a biological justification for a practice that controlled research and animal-welfare guidance challenge.
The appropriate question is not how little water a fish can survive in.
It is how much space, shelter, and environmental stability it needs to behave normally.
The Wild Horse That Somehow Disappeared
While discussing revisions to his mammal chart, Baker explains that domestic horses do not descend from today's feral horses.
That distinction is reasonable.
He then makes a much broader statement:
“Wild horses are just domesticated horses that have gone feral.”
Not all of them.
Przewalski's horse, native to the steppes of Central Asia, is widely recognised as the last surviving truly wild horse.
The Smithsonian's National Zoo distinguishes Przewalski's horses from the feral domestic horses found in North America and Australia.
Its research also acknowledges an important complication: genetic evidence has connected Przewalski's horses to ancient Botai horses, raising questions about whether their ancestors were ever managed or domesticated.
Nevertheless, the Smithsonian concludes that there is no strong evidence that Przewalski's horses are simply feral descendants of domesticated horses.
That qualification is precisely what Baker's sweeping statement loses.
The history of domestic horses is also better understood than his description suggests.
A major 2021 study published in Nature analysed 273 ancient horse genomes and identified the lower Volga-Don region of the western Eurasian steppes as the principal homeland of modern domestic horses.
The researchers traced the rapid expansion of the modern domestic-horse lineage across Eurasia from approximately 2000 BC.
The exact ancestral population and the history of domestication remain subjects of research. But scientists are not simply staring at an unidentified prehistoric horse and guessing where domestic animals came from.
There are two separate questions: which surviving horses are genuinely wild, and which ancient populations gave rise to modern domestic horses.
Baker's explanation does not preserve that distinction.
For a project built around evolutionary ancestry, that is a serious omission.
Jonathan Is Remarkable. The Greenland Shark Is Older.
The video introduces Jonathan, the famous giant tortoise living on St Helena, as an exceptionally old animal.
Baker describes him as the oldest living tetrapod or vertebrate.
The first description is defensible as a reference to the oldest known living four-limbed vertebrate. The second is misleading.
According to Guinness World Records, Jonathan was approximately 194 years old in 2026, based on an estimated birth around 1832.
He holds the distinction of being the oldest known living land animal.
But land animals are not the only vertebrates.
In 2016, researchers published a remarkable study in Science examining the ages of Greenland sharks.
They analysed the eye lenses of 28 female sharks using radiocarbon dating.
Their findings indicated a lifespan of at least 272 years, with the largest specimen estimated to have been 392 years old, plus or minus 120 years.
The research identified Greenland sharks as the longest-lived vertebrates known to science.
There is an important distinction here: the study estimated the age of sampled sharks, not the age of a particular Greenland shark confirmed alive today. Jonathan's record concerns an identifiable living individual.
But that does not make him the oldest vertebrate in the broader biological sense.
The Greenland shark's extraordinary lifespan also has consequences beyond record books.
An animal that may take more than a century to reach reproductive maturity is potentially vulnerable to population losses that could take generations to replace.
That is an evolutionary and conservation story worth explaining.
Baker's chart includes sharks. His discussion of longevity overlooks one of their most remarkable biological characteristics.
A Snake Family Is Not a Safety Guide
Baker's treatment of colubrid snakes illustrates another danger of simplifying animal classification.
He correctly explains that the family includes many familiar, relatively harmless snakes, including garter snakes and grass snakes.
He acknowledges that some members may possess venom.
But his general reassurance risks leaving viewers with the impression that colubrids are overwhelmingly creatures they need not worry about.
The boomslang offers an important counterexample.
This African snake belongs to the colubrid family and possesses medically significant venom capable of producing severe disturbances in blood clotting.
A 2023 medical case report documented a patient suffering severe boomslang envenomation who required three vials of specialised antivenom.
The authors also warned that access to the appropriate antivenom can be limited because serious boomslang bites are relatively uncommon.
Baker's qualification that some colubrids are venomous prevents his account from being categorically false.
But it remains an inadequate explanation of why a taxonomic family cannot reliably be used to judge whether an unfamiliar snake is dangerous.
Most members of a family can be harmless while an exceptional member presents a serious medical risk.
The exception is part of the information readers need.
When the Taxonomy Expert Gets the Taxonomic Rank Wrong
Another mistake occurs when Baker discusses the tuatara, a rare reptile found in New Zealand.
He initially identifies three living reptile orders, remembers the tuatara, and corrects the count to four.
He then describes the tuatara as belonging to a class of its own.
It does not.
Tuatara belong to the reptile class, Reptilia, and represent the sole surviving lineage of the order Rhynchocephalia, also called Sphenodontia.
New Zealand's Department of Conservation explicitly identifies the tuatara as the surviving representative of an ancient reptile order.
This distinction may seem small.
But distinguishing classes from orders is among the most basic tasks of a classification chart.
A mammal is not an order simply because it is unusually distinctive. Likewise, the tuatara does not become a separate class because its closest relatives disappeared millions of years ago.
Baker catches one mistake in real time but introduces another while correcting it.
The episode was deliberately recorded without his usual editing. That explains why such slips survived into the video.
It does not change what viewers hear.
Even the Explanations of Familiar Animals Need More Care
The problems extend to the mechanisms behind familiar biological adaptations.
Baker describes geckos as possessing suction-cup feet that allow them to climb walls.
But gecko adhesion is not fundamentally a suction mechanism.
In 2002, researchers published experimental evidence in Proceedings of the National Academy of Sciences establishing that microscopic structures on gecko toes adhere through intermolecular forces known as van der Waals interactions.
Their findings explained how geckos can stick to a wide variety of surfaces without relying on ordinary suction.
That is not a minor linguistic distinction.
The true mechanism is a fascinating example of how evolution can produce an adhesive system unlike the familiar devices humans use.
Baker's shortcut removes the very biological explanation that makes the animal interesting.
A similar problem appears in his discussion of axolotls.
He correctly identifies their retention of juvenile characteristics, known as paedomorphosis, and their extraordinary capacity to regenerate limbs.
He then links those features as though remaining juvenile explains their regenerative abilities.
The actual relationship is more complicated.
Research published in 2014 found that experimentally induced metamorphosis reduced the speed and accuracy of limb regeneration in axolotls.
But metamorphosed axolotls could still regenerate limbs, and regenerative abilities also occur in other adult salamanders.
Paedomorphosis matters. It is not a complete explanation of regeneration.
In both examples, Baker begins with a genuine biological phenomenon and replaces its complex mechanism with an explanation that is easier to remember.
Ease of understanding should not come at the expense of understanding the thing itself.
The Plant Chart Exposes a Deeper Confusion
Near the end of the episode, Baker discusses a major development in flowering-plant classification.
The Angiosperm Phylogeny Group's fifth classification, APG V, was published in 2026.
Baker explains that the updated system moves the former COM group—Celastrales, Oxalidales, and Malpighiales—into the malvids and restricts fabids to four major orders.
These changes are supported by the published scientific classification.
The APG V researchers drew upon extensive analyses of nuclear and plastid genes to revise relationships among flowering plants.
The problem arises when Baker explains what connects the plants within the fabid group.
He includes roses, oaks, cucumbers, pumpkins, peas, and beans, then tells viewers that they share the characteristic of nitrogen fixation.
That statement confuses membership in the evolutionary grouping called the nitrogen-fixing clade with the actual ability of individual plants to form nitrogen-fixing symbioses.
The distinction is considerable.
A study published in New Phytologist explained that the nitrogen-fixing clade contains 28 plant families, but only 10 include species capable of forming nitrogen-fixing root nodules.
Within most of those families, the majority of species lack that capability.
Nitrogen fixation involves specialised relationships with microorganisms. It is not a universal characteristic of every rose, oak, cucumber, or pumpkin.
The group's name describes an important evolutionary association, not a biological guarantee possessed by every descendant.
This is a particularly revealing error because it cuts directly to the purpose of phylogenetic classification.
An evolutionary tree identifies relationships among organisms.
It does not establish that every member of a branch possesses every characteristic associated with that branch.
Indeed, the APG V researchers themselves emphasise that conflicting genetic signals, ancient hybridisation, and uncertain relationships complicate the construction of a single evolutionary tree.
The science is more interesting than the simplified diagram suggests.
And understanding those complications is part of understanding evolution.
The Unanswered Question: What Reaches the Printed Charts?
Baker repeatedly tells viewers that the charts remain open to revision.
He describes incorporating suggestions about missing animals, ancestral relationships, extinct species, and classification details.
He also acknowledges that he knows less about reptiles, amphibians, and fish than about some other sections of the tree of life.
That admission makes the project's method especially important.
The video functions partly as a public review process: viewers examine the material, identify mistakes, and suggest corrections.
But there is a difference between asking viewers to improve an educational product and having a systematic process for checking its scientific claims before publication.
The mistakes identified here can be verified against research published years before this video.
The study establishing the physical mechanism of gecko adhesion appeared in 2002.
The Greenland shark longevity research appeared in 2016.
The betta welfare experiment appeared in January 2024.
None required a new scientific discovery during the chart's production.
The available evidence establishes errors and misleading explanations in the video. It does not establish that those errors appear on the final printed charts, which would require a separate examination of the finished products.
That distinction is essential. A spoken mistake is not proof of a defective poster.
Nevertheless, the project's educational ambitions and commercial distribution make the quality of its verification process a legitimate subject of scrutiny.
A viewer's correction may improve a chart. It does not necessarily reach everyone who already watched the original explanation.
The Verdict: A Beautiful Family Tree Is Not a Scientific Reference
The most damaging weakness in Baker's presentation is not an obscure argument about where one species belongs.
It is the repeated substitution of memorable simplifications for important biological distinctions.
A betta's ability to survive in shallow water becomes an explanation for keeping it in a tiny bowl.
A common truth about feral horses becomes a statement that overlooks the surviving wild horse lineage.
A tortoise's extraordinary terrestrial longevity becomes a claim that disregards the much longer potential lives of Greenland sharks.
And a group of plants associated with nitrogen-fixing symbioses becomes a collection of species supposedly sharing that ability.
These mistakes do not establish dishonesty, deliberate misinformation, or a fundamentally invalid evolutionary tree.
They establish something more specific: Baker's public explanation of the tree contains errors that competent scientific checking could have caught.
The central evolutionary relationships he presents are often well established. His willingness to incorporate corrections is also evident.
But those facts cannot settle the question of whether the finished educational material is sufficiently accurate.
That requires examining the charts themselves.
Until then, the clearest judgment concerns the video.
UsefulCharts succeeds in making the tree of life approachable. It is less reliable when explaining what some of its branches actually mean.
And when an explanation influences how someone understands an endangered animal, recognises a dangerous snake, or cares for a living fish, that distinction matters.
A diagram can simplify evolution.
It should not simplify away the truth.
References
1. Original work: Family Tree of Fish, Amphibians & Reptiles. UsefulCharts, Matt Baker, 2026.
Watch the original video
The primary source for Baker's explanations, qualifications, and statements challenged in this article; the supplied transcript was used to establish his exact claims.
2. Oldfield, R. G., and Murphy, E. K. — Life in a Fishbowl: Space and Environmental Enrichment Affect Behaviour of Betta splendens. Animal Welfare, Cambridge University Press, January 2024.
Read the research
Controlled observations establish that small bowls suppress normal swimming behaviour and that at least 10 litres are needed for its full expression.
3. How Should I Care for My Siamese Fighting Fish? RSPCA Australia, May 2024.
Read the animal-welfare guidance
Recommends at least 10 litres, preferably 20 litres or more, alongside suitable heating, filtration, and environmental enrichment.
4. Przewalski's Horse. Smithsonian's National Zoo and Conservation Biology Institute, undated.
Read the Smithsonian account
Distinguishes surviving wild horses from feral domestic horses while addressing unresolved questions about ancient Botai ancestry.
5. The Origins and Spread of Domestic Horses from the Western Eurasian Steppes. Nature, October 2021.
Read the genetic research
Uses 273 ancient genomes to identify the principal geographic origin and subsequent expansion of modern domestic horses.
6. Jonathan the Tortoise: The World's Oldest Terrestrial Animal. Guinness World Records, 2026.
Read Jonathan's verified records
Establishes Jonathan's estimated age and the terrestrial scope of his longevity record.
7. Nielsen, J., et al. — Eye Lens Radiocarbon Reveals Centuries of Longevity in the Greenland Shark. Science, August 2016.
Read the original study
Documents radiocarbon-based age estimates supporting Greenland sharks as the longest-lived vertebrates known.
8. Case Study: Boomslang Envenomation in North-Eastern South Africa. Medical case report, 2023.
Read the case report
Documents severe envenomation from a colubrid snake and the importance of specialised antivenom.
9. Tuatara. New Zealand Department of Conservation, undated.
Read the official species information
Identifies tuatara as the surviving representative of a reptile order rather than a separate class.
10. Autumn, K., et al. — Evidence for van der Waals Adhesion in Gecko Setae. Proceedings of the National Academy of Sciences, August 2002.
Read the experiment
Establishes the physical mechanism behind gecko adhesion, contradicting an ordinary suction-cup explanation.
11. Monaghan, J. R., et al. — Experimentally Induced Metamorphosis in Axolotls Reduces Regenerative Rate and Fidelity. Regeneration, 2014.
Read the research
Shows that metamorphosis affects regeneration without eliminating the capacity, making a simple juvenile-state explanation inadequate.
12. Angiosperm Phylogeny Group — Large-Scale Nuclear and Plastid Phylogenomic Analyses Inform an Updated Angiosperm Phylogeny Group Classification: APG V. Journal of Systematics and Evolution, 2026.
Read APG V
Confirms the flowering-plant classification changes and documents the genetic evidence and uncertainties underlying the revision.
13. Functional and Comparative Genomics Reveals Conserved Noncoding Sequences in the Nitrogen-Fixing Clade. New Phytologist, 2022.
Read the scientific paper
Establishes that nitrogen-fixing root-nodule symbiosis occurs in only some families and species within the wider evolutionary clade.