Ranked: The Life Expectancy of Humans and 49 Other Animals
Connect with us

Science

Ranked: The Life Expectancy of Humans and 49 Other Animals

Published

on

life expectancy of humans compared to animals

Ranked: The Life Expectancy of Humans and 49 Other Animals

For most of history, average life expectancy at birth for humans has stood around 30 years. But thanks to recent breakthroughs in technology and modern medicine, humans are now born with an average life expectancy closer to 80 years.

Some might argue this is one of mankind’s greatest achievements. With this rise in life expectancy, how do human lifespans now rank compared to other animals?

This graphic from Alan’s Factory Outlet covers the life expectancy of 50 different animals ranging from amphibians to arthropods, and even includes one species that’s immortal (well, in theory).

Let’s take a closer look at lifespans in the animal kingdom.

The Longest Living Things

Here are some of the longest living animals, where even with advancements in modern medicine, humans are likely far off from matching.

The Deep-Sea Tube Worm

The deep-sea tube worm, also known as Riftia pachyptila, lives until about 250 years old, though in some cases this can stretch much further.

Amazingly, they have no digestive system, mouth, or anus, and thus do not consume food to survive in a traditional sense. Instead, the bacteria living inside their bodies helps to transform the sulfur from nearby hydrothermal vents into energy.

This makes the deep-sea tube worm one of the few animals on Earth that does not derive its nutrients (either directly or indirectly) from sunlight.

The Immortal Jellyfish

The immortal jellyfish, otherwise known as Turritopsis dohrnii, is biologically immortal.

How is this possible?

Essentially, these creatures revert and transition backwards from sexual maturity towards sexual immaturity in a process called transdifferentiation—where adult cells are converted into other types of tissue. Not surprisingly, processes like these are getting plenty of human attention in gene therapy and scientific research.

Giant Barrel Sponge

The giant barrel sponge can live for 2,300 years. These cool creatures live on the reef surface of the ocean, and are bowl shaped, which provides habitat for many other invertebrates including crabs, shrimps, as well as fish. In addition, sponges have no tissue and each of their individual cells can do the same job of any other cell.

Some experiments have even shown sponges reform and have their cells swim back together when blended up in a blender. If they didn’t, that would be a very cruel experiment.

Human Lifespans: A Rising Trend To Watch

The number of centenarians—those 100 or more years old—stands at 570,000 today.

Here are the countries where they are most common compared to their respective populations.

Country/Region% Of Population
Japan0.062%
Uruguay0.061%
Hong Kong0.047%
Puerto Rico0.045%
France0.030%
Spain0.028%
Italy0.028%
Cuba0.027%

While figures in the one-hundredth of a percent range may sound underwhelming, this is still a 1,500% jump from the 33,000 centenarians that lived in the 1950s.

Slowly but surely, as human life expectancy continues to grow, our species seems destined to climb up the age ladder—and who knows, we may even be able to eventually live beyond some of the other creatures on this list.

Click for Comments

Science

Visualizing the Relationship Between Cancer and Lifespan

New research links mutation rates and lifespan. We visualize the data supporting this new framework for understanding cancer.

Published

on

Cancer and lifespan

A Newfound Link Between Cancer and Aging?

A new study in 2022 reveals a thought-provoking relationship between how long animals live and how quickly their genetic codes mutate.

Cancer is a product of time and mutations, and so researchers investigated its onset and impact within 16 unique mammals. A new perspective on DNA mutation broadens our understanding of aging and cancer development—and how we might be able to control it.

Mutations, Aging, and Cancer: A Primer

Cancer is the uncontrolled growth of cells. It is not a pathogen that infects the body, but a normal body process gone wrong.

Cells divide and multiply in our bodies all the time. Sometimes, during DNA replication, tiny mistakes (called mutations) appear randomly within the genetic code. Our bodies have mechanisms to correct these errors, and for much of our youth we remain strong and healthy as a result of these corrective measures.

However, these protections weaken as we age. Developing cancer becomes more likely as mutations slip past our defenses and continue to multiply. The longer we live, the more mutations we carry, and the likelihood of them manifesting into cancer increases.

A Biological Conundrum

Since mutations can occur randomly, biologists expect larger lifeforms (those with more cells) to have greater chances of developing cancer than smaller lifeforms.

Strangely, no association exists.

It is one of biology’s biggest mysteries as to why massive creatures like whales or elephants rarely seem to experience cancer. This is called Peto’s Paradox. Even stranger: some smaller creatures, like the naked mole rat, are completely resistant to cancer.

This phenomenon motivates researchers to look into the genetics of naked mole rats and whales. And while we’ve discovered that special genetic bonuses (like extra tumor-suppressing genes) benefit these creatures, a pattern for cancer rates across all other species is still poorly understood.

Cancer May Be Closely Associated with Lifespan

Researchers at the Wellcome Sanger Institute report the first study to look at how mutation rates compare with animal lifespans.

Mutation rates are simply the speed at which species beget mutations. Mammals with shorter lifespans have average mutation rates that are very fast. A mouse undergoes nearly 800 mutations in each of its four short years on Earth. Mammals with longer lifespans have average mutation rates that are much slower. In humans (average lifespan of roughly 84 years), it comes to fewer than 50 mutations per year.

The study also compares the number of mutations at time of death with other traits, like body mass and lifespan. For example, a giraffe has roughly 40,000 times more cells than a mouse. Or a human lives 90 times longer than a mouse. What surprised researchers was that the number of mutations at time of death differed only by a factor of three.

Such small differentiation suggests there may be a total number of mutations a species can collect before it dies. Since the mammals reached this number at different speeds, finding ways to control the rate of mutations may help stall cancer development, set back aging, and prolong life.

The Future of Cancer Research

The findings in this study ignite new questions for understanding cancer.

Confirming that mutation rate and lifespan are strongly correlated needs comparison to lifeforms beyond mammals, like fishes, birds, and even plants.

It will also be necessary to understand what factors control mutation rates. The answer to this likely lies within the complexities of DNA. Geneticists and oncologists are continuing to investigate genetic curiosities like tumor-suppressing genes and how they might impact mutation rates.

Aging is likely to be a confluence of many issues, like epigenetic changes or telomere shortening, but if mutations are involved then there may be hopes of slowing genetic damage—or even reversing it.

While just a first step, linking mutation rates to lifespan is a reframing of our understanding of cancer development, and it may open doors to new strategies and therapies for treating cancer or taming the number of health-related concerns that come with aging.

Continue Reading

Misc

Is it Possible to Bring Back Extinct Animal Species?

This graphic provides an introduction to de-extinction, a field of biology focused on reviving extinct animal species.

Published

on

Is it Possible to Bring Back Extinct Animal Species?

View a higher resolution version of this infographic.

Humanity has been tinkering with natural life for thousands of years.

We’ve become remarkably good at it, too—to date, we’ve modified bacteria to produce drugs, created crops with built-in pesticides, and even made a glow-in-the-dark dog.

However, despite our many achievements in the realm of genetic engineering, one thing we’re still working on is bringing extinct animals back to life.

But scientists are working on it. In fact, there’s a whole field of biology that’s focused on reviving extinct species.

Using data published in Science News, this graphic provides a brief introduction to the fascinating field of science known as resurrection biology—or de-extinction.

The Benefits of De-Extinction

First thing’s first—what is the point of bringing back extinct animals?

There are a number of research benefits that come with de-extinction. For instance, some scientists believe studying previously extinct animals and looking at how they function could help fill some gaps in our current theories around evolution.

De-extinction could also have a beneficial impact on the environment. That’s because when an animal goes extinct, its absence has a ripple effect on all the flora and fauna involved in that animal’s food web.

Because of this, reintroducing previously extinct species back into their old ecosystems could help rebalance and restore off-kilter environments.

There’s even a possibility that de-extinction could slow down global warming. Scientist Sergey Zimov believes that, if we were to reintroduce an animal that’s similar to the woolly mammoth back to the tundra, it could help repopulate the area, regrow ancient plains, and possibly slow the melting of the ice caps.

How Does it Work?

The key element that’s needed to re-create a species is its DNA.

Unfortunately, DNA slowly degrades, and once it’s gone completely, there’s no way to recover it. Researchers believe DNA has a half-life of 521 years, so after 6.8 million years, it’s believed to be completely gone.

That’s why species like dinosaurs have virtually no chance of de-extinction. However, many organisms that went extinct more recently, like the dodo, could have a chance of conservation.

When it comes to de-extinction, there are three main techniques:

① Cloning

This is the only way to create an exact DNA replica of something.

However, a complete genome is needed for this, so this form of genetic rescue is most effective with recently-lost species, or species that are nearing extinction.

② Genome Editing

Genome editing is the manipulation of DNA to mimic extinct DNA.

There are several ways to do this, but in general, the process involves researchers manipulating the genomes of living species to make a new species that closely resembles an extinct one.

Because it’s not an exact copy of the extinct species’ DNA, this method will create a hybrid species that only resembles the extinct animal.

③ Back-Breeding

A form of breeding where a distinguishing trait from an extinct species (a horn or a color pattern) is bred back into living populations.

This requires the trait to still exist in some frequency in similar species, and the trait is selectively bred back into popularity.

Like genome editing, this method does not resurrect an extinct species, but resurrects the DNA and genetic diversity that gave the extinct species a distinguishing trait.

Is Bringing Back Extinct Animal Species Really Worth it?

While there’s a ton of buzz and potential around the idea of bringing back extinct animal species, there are a few critics that believe our efforts would be better spent on other things.

Research on the economics of de-extinction found that the money would go farther if it was invested into conservation programs for living species—approximately two to eight times more species could be saved if invested in existing conversation programs.

In an article in Science, Joseph Bennett, a biologist at Carleton University in Ottawa, said “if [a] billionaire is only interested in bringing back a species from the dead, power to him or her.”

Bennett added, “however, if that billionaire is couching it in terms of it being a biodiversity conservation, then that’s disingenuous. There are plenty of species out there on the verge of extinction now that could be saved with the same resources.”

Continue Reading

Subscribe

Popular