#kevin: so i have access to dna from So Many Species | Explore Tumblr Posts and Blogs

kariachi · 29 days

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Who wants some fanfiction based on Kevin not actually being a great example of what an Ossy is capable of? It's not a 'okay but these fuckers are terrifying' fic, but still.

Kevin is put in front of a grown, trained Osmosian.

Cringing as he went flying across the room, the team tensed against the urge to go check Kevin was alright. Instructor Lonin called something across the space in Imperial Osmosian, and Kevin snapped back a response with words they hadn’t realized before this visit were stilted at best. For all the time any of them had known him he had been the resident expert on Osmosians- it was difficult not to be when you were the only one around- but here, watching him pick himself up off the ground with sharp teeth bared, they were reminded of just how isolated from his people he’d been. The language he only spoke just well enough, songs and stories he half-remembered, rules of etiquette he barely knew better than them. How quickly he was overpowered when he threw himself forward again.

None of them were used to seeing someone out strength him, so few managed, but Lonin made it look easy. Lashing out to clamp one hand around his arm, they yanked him down and to the side enough that grabbing his other limb let them twist it behind his back. In a heartbeat he was on the ground, one arm pinned painfully beneath and the other behind, a knee on his hip and teeth around his neck. Still snarling, Kevin struggled once, twice, before the teeth tightened and he finally went begrudgingly still.

Rook reached over to lay a hand over Gwendolyn’s, a silent reminder against her tension that he was in no real danger. That she had been the one to recommend that he should do more than just visit the homeworld but try to learn. At her other side, Ben watched with interest that could only come from someone who had had to fight the species before and worried he would again.

For what felt like an age the pair stayed on the floor, Kevin glaring back as best he could as Lonin growled low. Slowly, once they were sure he wouldn’t continue fighting, they removed their knee. Released the arm pinned beneath his body. The one behind his back. Only after all that did they open their jaw and pull away.

Deftly dodge the elbow he threw back.

Grabbing hold, they cast him to the floor again. This time landing on his side, he only had a moment to twist and try to bite before they’d used his arm to pin his head to the floor, straddling his legs to keep them still. Kevin managed to get his free palm solid against the stone floor a moment before Lonin did. For a heartbeat it looked like he might gain enough strength to throw the older Osmosian off, but only managed in jostling the both of them before they also had a full mass. Still, he railed against them, thrashing enough test their grip in the seconds before they encased his body in stone.

There was no careful slowness as they stood this time, just ease and the same impassive expression they’d worn for the past half hour at least.

“You really haven’t gotten any kind of training,” they said in a tone that edged towards disappointment. Pinned from knee to shoulder, Kevin glared up at them.

“Not exactly a lot of Ossys in my part of space,” he said.

“It shows.” They huffed, grumbling something in Imperial as they circled Kevin. For far from the first time the rest of the team regretted taking moments like this to try to improve their Galactic Standard. “Have you had any sort of proper practice?”

“I do use my powers,” Kevin grumbled, fidgeting as much as he was able. “Been mostly absorbing and manipulating solids for… a long time. I’m pretty good shapeshifting with them, and-” He threw a quick glance to the others, took a breath. “-I’m damn good at shapeshifting with copied DNA.” Lonin made a thoughtful sound.

“I suppose you would get a lot to work with, running with The Great Ben 10,” they said in a tone that implied they weren’t all that impressed with the hero. “If you’re a good shapeshifter, you won’t have any trouble freeing yourself then.” As simple as that they turned and walked away, taking a seat within Kevin’s view but a good distance to the side.

Again the team shared a look. A silent question whether they should intervene. The entire reason they had come along was to act as emotional support, for all he’d tried to hide it Kevin had been nervous to spar with another adult Ossy, but now they didn’t know what to do. They didn’t know if this was a normal Osmosian thing, or even a reasonable request. It certainly didn’t seem like one.

Still, for all their concern, Kevin merely took a deep breath and began shifting his shape again. Everyone watched as, with the tentative slowness of someone unpracticed in a specific act, he stretched out his arm. The team all but held their breath as it stretched farther and thinner, followed by shoulders, his other arm working its way free. He was able to get a grip on the distant floor, and used it to slowly drag his lengthened body out of it’s prison. Everything seemed to contract back into the proper shape as he did. Once everything was back in place, he rolled his joints with a deep sigh. Lonin made a purring, trilling noise at him.

“Not a bad job, for someone who didn’t grow up in the tunnels,” they said. Kevin’s cheeks took on color as he glowered at them. “So, you can do basic shapeshifting.”

“With solids,” he clarified. “With DNA I can do partial, full, and combined shifting.”

“And just how much practice do you actually have there?” Fidgeting again, Kevin threw another glance to his team, who tried to give him encouraging smiles. They didn’t seem to help.

“I’ve got access to at least thirty-four sapients, two non-sapients, and I don’t know how many plants. I don’t like using them if I don’t have to, but I can.”

Lonin froze, staring at him with wide eyes and dipped chin. They muttered, almost growled, something under their breath in Imperial.

“Alright,” they eventually said, just before things got too awkward, “let’s move right passed that for now, then.” A weight seemed to come off Kevin’s shoulders. “What about other forms of matter?”

And fell right back on.

“I’ve done demi-solids, twice,” Kevin said with some uncertainty, “and I haven’t touched liquids or gases.”

“Good,” Lonin said. “I still hardly touch gases if I don’t have to. Liquids are easier though, as long as you have a proper teacher.” Kevin nodded.

“Supposedly my dam was better with liquids than anything else, but…” He shrugged.

“They can be dangerous to learn, avoiding testing them was smart.” Head just barely tilting, Lonin threw what was almost a glance towards the rest of the team. “And what about energy?” Everyone tensed.

“He avoids it,” Gwendolyn answered before Kevin even got the chance, earning a sharp look from Lonin. Only once she’d sunk back in her seat did they turn back.

“Got addiction issues,” Kevin said, tense as a bowstring, “and I tend to get, nasty, when I’ve absorbed a lot of it.” With a curious noise, Lonin blinked.

“Are you prone to overload then?” Kevin blinked. Threw a look at the others. They all shrugged. More often than not, he knew more than them about these things.

“Maybe?” Lonin rumbled.

“Do you become more violent when you absorb energy, or when you absorb large amounts of energy?” For a long moment the youngsters were quiet, Kevin chewing his lip as he considered the question.

“Both? I’m nasty when I’ve been absorbing energy, but I get worse the more I do.”

“Alright then.” They gave another purring trill. “Energy overload isn’t an uncommon problem, and there are plenty of ways to work around it and addiction both, but again it’s smart of you to avoid energy without someone to teach you such techniques.” Kevin let loose a breath as the team looked between themselves again. The concept that using energy safely was an option hadn’t occurred to anybody. Not with Kevin’s history, and not after Aggregor.

“So, I’m not doing too bad then,” he said with a little half smile that didn’t fully reach his eyes. Lonin made a noncommittal noise.

“Your solid matter usage is far behind others your age” they said, “you have no training with energy, no experience with liquids at all. You’ve clearly seen combat, but have no idea how to properly use your powers in it. I taught soldiers for two-hundred years and if I had ever been sent an apprentice in such a state, I’d have fought both their Clanhead and Packhead personally.” The smile slipping from his face, Kevin clenched his fists, dipping his head and flashing a glimpse of teeth.

“So…”

With an ease that belied their age, Lonin stood back up, dropping the stone they’d absorbed. They looked Kevin over, flexed their fingers, and made the purring trill again.

“You have until this time tomorrow to decide if you want to learn, and if you do, I suggest finding long-term quarters.” As Kevin relaxed minutely and Gwendolyn chewed her lip, Lonin spared him what almost looked like an approving expression. “You have a lot of catching up to do.”

#fanfic #i still want to write a 'okay but these fuckers are terrifying you don't understand kevin is a *child*' fic but this ended up not being tha #lonin: *expects working with ben to have led to kevin absorbing from like three or four species- kinda equivalent to having nailed them*#kevin: so i have access to dna from So Many Species #lonin: .......we aren't going to unpack that here but if I ever find whoever was in charge of looking out for you-

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redrobin-detective · 3 years

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love language

“Ben,” the voice said softly, “wake up.” It was familiar in a way Ben couldn’t put his finger on.

“No, mom,” Ben groaned, “five more minutes.”

“Not Mother,” the voice said with an amused huff. “Been longer than five minutes, worried now,” it continued on awkwardly. Ben frowned, confused by the situation. He opened his eyes and sat up to assess what was going on. At least that was what he tried to do.

“Woah,” he gasped as he found he couldn’t move much at all. He didn’t really have sensation or form, there was nothing around him to see and no eyes he could use to see anything with. Ben felt like his brain was spread thin, like cream cheese on a bagel, making every thought feel strange and disconnected. “Where am I?”

“Safe,” the voice soothed and Ben couldn’t help but believe. “Always safe with me. We’re away from attack now, recover here for Grandpa Max or Cousin Gwen to find us.”

“Us?” Ben fumbled as he added up the words in his head. “Wait, you’re the Omnitrix, aren’t you?”

“Yes,” the voice - which now that he was listening Ben recognized as his own just a slightly different pitch and intonation - said happily. “And you are Master, Ben Tennyson.”

“So wait, am I inside the watch?” Ben asked. That would explain his lack of a body, his whole brain was just floating around inside the alien device. It was weird and a bit scary, no wonder Ghostfreak didn’t like it. “Are you in my body?”

“Sorry,” the Omnitrix said almost apologetically, “was necessary. You were unconscious, your life threatened. Had to access your nervous system to get you to safety. Switch back now?”

“No wait, not yet, I wanna talk some more,” Ben pleaded. “Could you always do this? I feel Azmuth would have shadowbanned me ages ago if he knew he could.”

“This was an emergency, we will always do what is necessary to save the Master’s life.” the Omnitrix responded, it’s words coming more naturally now that it was getting used to it. Ben could practically feel the device flicking through his knowledge language and vocabulary to better communicate. It should feel invasive and yet somehow wasn’t. “And Creator does not get an opinion on the Master.”

“Harsh,” Ben responded back, “what do you got against Azmuth? He did make you, helps fix you when I mess up even though he doesn’t have to.”

“Creator tried to separate us,” the Omnitrix bit back harshly. “He lied to Master, drugged you and attempted to remove me from your person. It did not ask either of us, simply decided a child could not handle the responsibility.”

“Woah,” Ben had gone to Galvan Prime many times, fallen asleep quite often. How many times had Azmuth tried to take the device from him?

“Only once,” the Omnitrix chimed in as if reading his thoughts which, oh, it probably was. Weird. “We shocked him to unconsciousness, to prevent him from trying again. We will not be separated.”

“Protective, aren’t you?” Ben chuckled awkwardly. It was one thing to know Azmuth wanted to remove the watch, it was another to realize the watch wouldn’t let that happen.

“You are the Master,” it said fondly, “We love you, more than anything in the omniverse. We would watch it all burn if it meant keeping you safe.”

“What?” Ben asked flustered. His parents said they loved him constantly, same with Grandpa and Gwen. But this felt different. “Why? Like seriously, why me? I’m 16 years old and I’m just as much a mess as I was at 10.”

“We...” it paused as if thinking. There was a vague feeling of moving and Ben wondered what the watch was doing in his body. “We can’t explain, Master was just right.”

“Many wanted to claim us,” the Omnitrix continued. “For many Earth years, we were pulled across the universe, searching for the perfect host. Creator grew tired of the debates, the lies, the deaths that followed and eventually abandoned us. It told us to choose wisely who could use our power. Kings and warriors and scientists demanded it and still we did not relent. None were worthy until you.”

“Seriously?” Ben questioned, “I was like a C student with unmanaged ADHD and about 4 complexes stuffed in a trench coat. Plus we met on accident, Xylene was trying to send you to Grandpa.”

“We like Grandpa Max,” the watch hummed, “but he is too much of solider. Sometimes he even forgets your his family. When the pod opened and we scanned you, we only found your curiosity and wonder. You were the first being to look upon us without ulterior motives. It was, nice.”

“I get that,” Ben mumbled to himself, more than used to everyone in his life expecting something or other from him.

“We, too, were curious about you. Creator did not add human DNA in our storage. He only cared for relevant species at the time, Earth and it’s people were as alien to us as we were to you.”

“Is that why you latched on?” Ben asked again.

“Partially, we knew were under attack and needed some manner of escape. It wasn’t going to be forever but we found we liked you; your bravery, your creativity, your love... it inspired us. You went from Host to Master and we bonded more permanently.”

“Huh,” Ben said thoughtfully. “I never really realized you were alive, that you chose me.” He chuckled sadly, “I turned out to be kind of a disappointment, huh?”

“No,” the watch responded forcefully, enough to startle Ben out of his dark thoughts. “We love you, all of you. All your successes and failures, flaws and strengths, we love them all. We are one in the same, bonded in entirety. We will spend the rest of your days together and when your natural death comes, we will die too. There will be no Master after Ben.”

“So even when I’m just messing around...” Ben asked, changing topics from that heavy comment.

“You taught us how to play and we learned,” The Omnitrix teased. “You ask for Humongosaur too much though, we can have our own fun.”

“Oh so you’re the reason I always get the wrong alien,” Ben laughed. “You’re gonna get me killed one day!”

“Never,” the Omnitrix said warmly but with a steely protectiveness in there. “We will always protect you.”

“Hmm, I guess so,” Ben hummed. “What’s going out in the real world?”

“The battle is over as far as we can see. No sign of Cousin Gwen, Friend Kevin or Partner Rook. Grandpa Max was still in the satellite orbiting the planet last we heard. Do you wish to return now that the danger has passed?”

“Nah, not yet,” Ben sighed, enjoying a few minutes without someone needing him. “I know my body is in safe hands. Tell me more about some of the bozos who tried to wear you.”

“Aurius the Magnificent was one of the more annoying,” the Omnitrix said in the tone Ben used when he was feeling petty. “Just put me on and demanded that I chose him. He did it in front of his whole court and was so frustrated when I would not attach. His concubines laughed at him.”

“Oh man, how embarrassing,” Ben cackled. He let go of his worries, of his responsibilities, of everything and just basked in the familiar tones and the omnipresent love around him.

#ben 10 #the dialogue hit me like a shot and I practically spider crawled out of the bath to reach my laptop #this would be like the prologue before the possessed omnitrix au I wont write #this is like half fic half meta lmao #just really wanted to impress on the watchs utter love for ben but also how scarily possessive it is #it knows him inside and out and chose him above all others #its too attached now (in all meanings of the word) it would kill the universe before it allowed ben to die #which is uhhhh something #watch also has Opinions on the people in Ben's life #esp Azmuth and Grandpa #but at least it has good memories of Max #its PISSED that Azmuth tried to separate them once like 6 years ago #anyway here's some whatever i cranked out in like 45 minutes #now dinner

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terribleben10opinions · 5 years

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Alien force balancing part the third

Alien force aliens too strong, me don’t like, gonna change to make more interesting fights and higher stakes. Let’s end this exercise in proposing changes to a kids show that’s been off the air for like 7 years.

1. Chromastone

Current power set:

1. Energy absorption

2. Laser and shield generation from absorbed energy out of pink crystals

3. High durability

4. Flight (????)

Revised power set:

1. Energy absorption

2. Laser production from absorbed energy out of pink crystals

3. High durability provided he’s not full of energy

Chromastone’s species is related to Diamondhead’s and serves as a back up to all the minds of Tetrax’s species so I’d say he’s a sort of messiah for the Diamondhead species and I think that should be reflected in how Ben uses Chromastone. What if, instead of pure “absorb energy show out rainbows through hands” Ben had to concentrate to ensure the energy is coming out of his hands as opposed to any other of his pink crystals? I think possibly a “calm demeanour” restriction to actually use his powers foreshadows Chromastone's actual role and purpose and forces Ben to develop maturity and could maybe provide a cool scene where someone is kidnapped that Ben super cares about (probably Julie but I’d also love this with Kevin) and he uses Chromastone with deadly precision because he’s at this weird state of hyper rage calm and ultimate concentration and is DECIMATING whoever is keeping the kidnapped person hostage. For everyday use this would just mean Chromastone does more absorbing and can act as an energy sponge more, he could still shoot the lasers back he would just do less and they would have to be more accurate, putting more stress and importance on each shot. Second big change is Chromastone’s durability, I want him to be more susceptible to physical attacks when he’s more charged up with energy. I get that he’s made of probably a diamond like substance but having him invulnerable to energy and physical attacks is like that annoying twat in your class who had an everything proof shield during pretend games at recess NO TRISTAN WE CAN’T TELL ON YOU FOR THIS BUT STILL FUCK YOU WE DIDN’T EVEN WANT TO PLAY WITH YOU AND NOW LUCAS IS CRYING BECAUSE YOU’RE SUCH AN INSUFFERABLE FUCK HEAD. So the more energy Chromastone has got the more brittle he becomes meaning he can be durable or offensive but not both. This can be how Vilgax kills Chromastone also by charging him up WAY too much and Ben is freaking out so can’t expel the lasers out and then Vilgax just flicks him because the original battle was so lifeless and anticlimactic. Also can we please have Gwen shoot a load of mana into Chromastone when they’re surrounded and then destroy everything around them, that’d be sick.

2. Jetray

Current power set:

1. Supersonic -> light speed flight

2. Laser vision and tail

3. Durability to survive gunfire

4. No need for oxygen

Revised power set:

1. Supersonic flight and swimming

2. Ability to generate electricity around body like an electric eel

Jetray is one of the main reasons I started making these posts, in the OG series XLR8 was fast, Stinkfly could fly and heatblast had projectiles, in UAF Jetray does all of these and does them better meaning Jetray is rarely going to be in a situation where he’s out of his element. Jetray also has some of the highest bullshit levels I’ve ever seen, no need for oxygen??? Super speed in space??? GUNFIRE DURABILITY??? FUCKING LASERS???? Thats too much man. I’m taking away the Superman factor and just making him a fast flyer while also giving him the Superman blue factor and giving him a little bit of electricity. Jetray won’t be able to shoot the electricity or anything but he can zap people if he’s in direct contact with them, and of course he can do some problem solving with it like maybe holding a metal stick and using it as an cattle prod or Kevin absorbs some metal and Jetray supercharges him making him basically Mjonir. There should also be a cool down on the electricity so not everything Jetray does is going to be zapping fools, there’ll also be just good old Jetray aerial combat. Just as a final little change I want to change the actually design to the one in the bottom right of this concept picture.

Tbh Jetray is super ugly and I’d rather him have this buggy face instead of the thumb with eyes and a mouth he currently has.

3. Humungousaur

Current power set:

1. Big strong dinosaur

2. Thick and durable hide

3. Ability to increase size and mass

Revised power set:

1. Big strong dinosaur

2. Thick and durable hide

3. Black spikes that Ben is able to shape into different dinosaur parts and maybe weapons

I am admittedly harsh with Alien force for it’s heinous crime of not being the show I watched when I was a child and thus less smart and full of criticism and anxiety and because of this I really try and give credit where credit is due with alien force but humungousaur is something I can’t give credit for. I know that the show is unrealistic and doesn’t have to adhere to normal physics but even in a world with a magic alien watch that has a person change mass and size, having humungousaur gain mass doesn’t make sense because humungousaur’s species don’t all wear those magic alien watches so I think they should take the omniverse route and quietly sweep his size changing under the rug. In addition I think they should take notes from the... 🤢 take notes in design from the r-🤢... TAKE NOTES FROM THE REBOOTED DESIGN 🤮🤮🤮.

Writing that makes the old man in me scream because the reboot Ben has FUCKED so many aliens (rip XLR8 & Wildvine) but they really did good with humungousaur. Really the design isn’t that different but I LOVE the black scales and I think it’d accent my proposed power change really which is to have those black spike form claws or triceratops horns or the normal mace on humungousaur’s tail essentially giving him the necrosword from marvel but with more dinosaur themes. (Real quick I only watch clips of the rebooted Ben 10 and I did see some pictures while writing this of humungousaurs with swords and shit on their tails so maybe I’m ripping this off but what are you gonna do huh? Call a cop?? I’ll just have sex with them 😎 ). This power change I think will give ben more routes of attack like headbutts using horns or tail swipes with the mace or even making all the black spikes go on his hand and unleashing a BEAT DOWN on someone. Honestly Humungousaur like Goop is a good boy who didn't really require a change it was just something that bothered me more than something on a kids show should bother someone.

4. Alien X

Current power set:

1. Anything?

Revised power set:

1. Still anything

Ah Alien X, basically the antithesis to this whole time sink I’ve forced upon myself. Okay another cop out but Alien X was a really really good concept, it’s weird that the universe personified as DNA but who cares, this literal god has proper balances to ensure he doesn't break the show and they used it sparingly enough to make sure it never felt cheap and always had weight. The fact that Gwen and Kevin had to both use keys to activate Alien X was a realistic and cool decision and gave a sense of actual danger when using it. The problem with all this though is that Ben then only really has 9 aliens because Alien X is never used, so my proposed change is to make Alien X the 11th alien and just pop LODESTAR in his place for 10th, EVERYTHING else would be the same just Ben would have access to Lodestar earlier and since LodeStar is a good good boy I don’t think he needs any changes.

Thanks everyone for reading this hot mess of a series, if weren’t clued off from the title alone theres 2 other parts in this series which are probably better because I used all the aliens I had ideas for power changes first and then went “shit, there’s still 4 left”.

#ben 10 #ben 10 alien force #ben 10 alien swarm #ben 10 ultimate alien #ben 10 omniverse

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ntrending · 6 years

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Look to large bodies to understand long life spans

New Post has been published on https://nexcraft.co/look-to-large-bodies-to-understand-long-life-spans/

Look to large bodies to understand long life spans

The tiny nematode known as Caenorhabditis elegans lives its entire life in about three weeks. The worm’s fleeting existence is just a fraction of the time allotted to centipedes or rats. These animals are in turn left in the dust by a horde of other creatures, from badgers to lions to chimpanzees. Even more impressive is the bowhead whale, whose 200-year life span is the longest of any mammal.

There are a few extreme outliers, animals whose lives stretch well beyond their closest relatives. One quahog clam reached 500 years of age—a life span that is about 8500 times longer than that of the humble nematode, says Matt Kaeberlein, a molecular biologist at the University of Washington in Seattle. The ancient clam could have fit on a dinner plate. Generally speaking, though, large animals like whales and elephants live a great deal longer than smaller ones like mice.

But how do they do it?

“My guess is there’s not going to be one answer,” Kaeberlein says. There seem to be a wide range of strategies that animals use to protect their DNA and tissues from the ravages of aging and outlive their peers. Scientists are determined to discover what they are in order to stave off age-related maladies like cancer, dementia, and heart disease in people.

The good news is we already have a pretty good idea why large animals often live longer than small ones. It has to do with the fact that tiny animals are more likely to be gobbled up by predators. These animals tend to have babies early and age quickly. “If you’re a mouse, there’s no selection pressure really there to solve problems relating to cancer or older age, because in all probability you’re dead by then, you never get to that stage,” says Kevin Healy, a macroecologist at the University of St Andrews in Scotland.

Bulky animals can afford to take a long time to grow up and reproduce. “If you’re an elephant, you’re not going to get eaten by a hyena, for instance, so being big has intrinsic advantages,” says João Pedro de Magalhães, a biologist who studies aging at the University of Liverpool in the United Kingdom. So when an animal has a low risk of being killed by outside circumstances like food shortages or predators, it has a chance to evolve a longer life span.

Some groups of animals live a lot longer than their body size alone would suggest, including many birds and bats. Healy and his colleagues have examined how different lifestyles like flying or burrowing might explain why this is. They found that the ability to fly was key to whether an animal would have a long life span. “It’s kind of like being really, really big,” Healy says. “If you fly you can evade your predators, you can move to new areas quite easily, if there’s a drought in one area you can move somewhere else.”

Animals that burrow far out of reach of predators might also have an advantage. However, there aren’t that many species that live underground, Healy says. The most noteworthy specimen—the naked mole rat, which can live over 30 years and barely seems to age or get cancer—might also have evolved its super-long life span for other reasons.

The naked mole rat behaves more like ants or termites than a typical rodent, Healy says. They live in colonies of workers presided over by a single queen who births all the pups. “They’re protecting the queen, so that no predators get near the queen, if there’s a food shortage it’s the queen that gets the food first, and so basically creating an environment that’s really protective and allows them to live much longer,” he says.

Primates tend to enjoy lengthy lives too, de Magalhães says. Chimpanzees live about twice as long as you’d expect based on their body size. And going by size alone, human beings ought to have a maximum life span of about 27 years. But the oldest person we know of lived to more than four times that; a French woman, Jeanne Louise Calment was 122 years and 164 days old when she died in 1997.

Comparing chimps to people isn’t entirely fair, de Magalhães says. Our maximum possible life span is probably skewed because we have access to medicine and by the fact that there are just so many more of us than other primates. Still, part of our ridiculously long life spans comes from our superior intellect; skills like being able to build and use tools probably gave us a survival edge, allowing us to evolve longer life spans over time.

“The evolutionary perspective of why larger animals live longer is well understood,” de Magalhães says. “What are the mechanistic bases of that? I think that’s less clear.”

Live fast, die young?

Scientists used to think that the main reason big animals live so much longer than smaller ones is that they have slower metabolisms.

“When you’re tiny like a mouse you have a lot of surface area per unit of volume and that means you’re radiating heat like crazy,” says Richard Miller, a biogerontologist at the University of Michigan in Ann Arbor. A big animal like an elephant needs to burn relatively less of its energy to stay warm. This means that animals with long life spans will also tend to have low metabolic rates. Scientists assumed that this put less wear and tear on their cells.

But metabolism is actually a red herring, Miller says. “Kangaroos and opossums have really low metabolism, and so if this idea were correct you’d expect them to have really long life spans. But in fact, they have really short life spans.” And birds and bats have high metabolisms, yet often live even longer than their body size would predict.

De Magalhães and his colleagues have examined whether there is any connection between life span and metabolic rate across mammals and birds. After they accounted for body size, the correlation vanished.

However, it is possible that metabolic rate plays a role in longevity for cold-blooded animals, whose body temperature depends on their environment. Some of the longest-lived creatures live in cold waters. These include the olm, a cave-dwelling salamander that may reach ages of 100 years; the orange roughy, a deep-sea fish, can live 150 years; and the Greenland shark, which lives to the ripe old age of 400 years. “Their metabolic rate is very low because, just like a furnace, if you turn up the heat we burn more energy,” Healy says.

What’s more, cold-blooded animals like nematodes and flies live longer when they are raised in colder temperatures, de Magalhães says. It’s possible that their cells accumulate damage more slowly under these conditions. It’s harder to test whether this might also be true for mammals, since our bodies stick within a much narrower range of temperatures.

“In the case of the very long-lived clams, I think it’s almost certainly the case that cold temperature is part of the story, but it’s not all of it,” Kaeberlein says. Other clams found in the same areas live for decades instead of centuries.

Similarly, some bats have outstripped even their flying peers. Brandt’s bat can live for 40 years despite being the size of a mouse. The best an actual mouse can hope for is 3 or 4 years. A bird the same size could expect to live around 10 years, Healy says.

“While we do see bigger things living longer, flying things living longer…the variation is really, really large,” Healy says. “It isn’t a universal pattern.”

Peeking under the hood

There are a certain markers of aging that show up across the animal kingdom. As we get older, our mitochondria—the tiny power plants that make energy for our cells—don’t work as well. Proteins begin to fold into the wrong shape and can build up in plaques in diseases like Alzheimer’s. Tiny caps called telomeres that protect our DNA get shorter until the cell can’t divide anymore. Mutations build up in our DNA. These and a few other processes seem to account for much of how our cells age over time.

We don’t know how much they explain the enormous differences in longevity among animal species, Kaeberlein says. However, many of these processes do appear to work differently in animals that have particularly impressive life expectancies. There’s evidence that telomeres in some bats—which have the longest life spans of any mammal relative to their body size—do not shrink with age. And long-lived clams and naked mole rats seem to be particularly good at keeping their proteins from misfolding, Kaeberlein says.

However, naked mole rats have plenty of other talents. One is their ability to produce a unique form of a sugar called hyaluronic acid that keeps skin elastic—and also suppresses tumors. The hyaluronic acid naked mole rats produce is five times larger than the version our own cells make. “This at least might be related to the reason why naked mole rats don’t develop cancer at anywhere near the rates that we would expect them to,” Kaeberlein says. “It wasn’t one of the hallmarks of aging that everybody thought about.”

Scientists are particularly enchanted by unusual cases like the naked mole rat. However, there are also a few patterns that seem to show up across long-lived animals.

These animals may be better able to cope with mutations and DNA damage than those with short life spans. Scientists are investigating these abilities in elephants and bowhead whales. “You would expect these animals that have way more cells than we do to have high cancer rates, but if they did so they wouldn’t live so long,” de Magalhães says. “So they must have tumor-suppressing mechanisms that we lack.”

Researchers have shown that elephants have extra copies of a gene involved in tumor suppression called p53. And de Magalhães and his colleagues have found that in long-lived animals—including bats, elephants, people, and other primates—genes that help cells withstand DNA damage seem to be evolving more quickly than in short-lived animals like rats and mice.

Animals with long life spans may also have hardier cells that are more resistant to stress, Miller says. He takes skin cells from different animals and bombards them with cadmium, hydrogen peroxide, and ultraviolet light. If the cells came from a long-lived creature like a porcupine, it takes a lot more of these noxious substances to kill them than if they came from a mouse.

“If you’re growing up as a mouse and very unlikely to live for a full year before you starve to death or get eaten, having metal-resistant cells doesn’t pay off very well,” Miller says. “But if you’re an elephant or a porcupine or a bat…evolved resistance to a vast range of toxic and physical insults is a really good thing.”

He and his team are looking into how cells in long-lived animals might become less sensitive to stress. They’ve identified one enzyme called thioredoxin reductase 2 that protects the mitochondria from damage and is nearly always found in greater amounts in cells from long-lived primates, birds, and rodents. What’s more, mice with a mutation that cause them to live longer than their fellows also produce more of this enzyme.

The researchers have also zeroed in on structures called immunoproteasomes that help cells break down damaged proteins. Long-lived birds, rodents, and primates all seem to share high levels of immunoproteasomes, and their cells are better at clearing out errant proteins those from short-lived animals. “These three groups evolved separately,” Miller says. “That’s a strong sign that you cannot evolve a long-lived species without all these immunoproteasomes.”

It can pay to be small

So if big animals live longer, what’s the deal with dogs? Smaller breeds like Chihuahuas can live beyond twice as long as the towering Great Dane. About 56 percent of the variation in life span among dog breeds can be linked to differences in body size, Miller says.

And it’s not just a purebred problem—the relationship between size and life span is just as strong in mixed-breed dogs, Kaeberlein says. Nor is it confined to dogs. Even though larger species tend to live longer than small ones, taller individuals within the same species will on average have shorter life spans. “The data are pretty compelling that, on average, bigger people tend not to live as long as smaller people, bigger mice tend not to live as long as smaller mice,” Kaeberlein says.

One of the culprits may be a hormone called insulin-like growth factor 1, or IGF-1, which encourages cell growth. In mammals and invertebrates, individuals with higher levels of this hormone grow larger. There’s evidence that mice and people with more IGF-1 also have a higher risk of cancer, Kaeberlein says. Having less IGF-1, on the other hand, is associated with slower aging and a longer life expectancy in worms, flies, and mice.

“We don’t really understand how these hormones go about creating an animal that is either normal or long lived,” Miller says. However, it’s possible that tinkering with IGF-1 or other related hormones could one day extend human life spans.

Because large dogs are so much larger than small dogs, the differences in longevity are especially dramatic. But there is a silver lining. Kaeberlein and his colleagues are testing whether a drug called rapamycin—originally discovered being secreted by soil bacteria on Easter Island—can extend healthy old age. When older mice are treated with the drug, their hearts become stronger and they live up to 60 percent longer. When elderly people are given a derivative of rapamycin, their immune systems respond to flu vaccines more like those of younger people. Kaeberlein and his team have been testing the drug in pet dogs, which suffer from many of the same age-related diseases as people.

“We’re doing this in large dogs for the very reason that large dogs age faster than small dogs,” he says. “We can actually asses whether something like rapamycin can improve heart function or improve cognitive function in a pet dog in a few years, whereas in a human that might take a decade.”

The drug is thought to work by making cells think that there are few nutrients available so they go into survival mode and don’t proliferate as much. This is similar to caloric restriction, another promising anti-aging strategy.

In a small first trial, the team saw that rapamycin seems to have similar cardiovascular benefits for large dogs as those seen in mice. The researchers are now enrolling dogs in a second, longer trial that would examine heart and cognitive health more closely. Their hope is that rapamycin could eventually be used to help your pooch—and you—live longer.

It’s not easy to figure out why a particular gene or facet of an animal’s environment can help it live longer, precisely because these animals tend to grow to unwieldy sizes and stick around for a long time. “A lot of these are still hypotheses, we can’t prove them yet because we can’t make transgenic or mutant elephants or whales,” de Magalhães says. He hopes to create a mouse with genes from these animals and examine how they affected its life span, though.

All of this means that we’re still at the beginning of identifying the secrets behind why large animals and oddballs like the naked mole rat live so long. “There doesn’t seem to be a one-size-fits-all, universal solution to aging,” Healy says. “It’s more likely to be almost jury-rigged, so different mechanisms to kind of patch up all the aging processes that are going on. The more of these we can find, the more possible solutions to diseases related to aging that we can also find and perhaps implement.”

Written By Kate Baggaley

#Animals

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