Submitted by marketrent t3_10xjcyd in science
Depends on place, time, presence of competition and how long since a major extinction event, and what else is around. Enough big prey animals to support sustainable groups of large predators, not enough major apex predators around to limit herbivore size etc.
Most extinction events hit the large species harder because they need more food to sustain their bodies, and a major hit to their diet goes very badly. In the time after though, after whatever went wrong is over or stabilized to a new normal, some of the smaller species start to grow to fill the gap left behind.
One reason for a marine animal to get bigger is insulation. Even warm water can draw heat from a body. It makes it easier to regulate your own body temperature and that means you can stay in the water for longer and travel further, and may reach harder to access food sources.
The time for giant penguins was between 60-23 million years ago. There were more than this one species. But they all died out.
Their fall coincides with the diversification of dolphins who might have competed for the same spot in terms of diet and size and they were much better at it, or they may have acted as predators to the penguins. Or both.
As for place several of these giant penguin species have been found in or near new Zealand. At their time there was also the Zealandia continent, which since around 23 million years ago is almost completely submerged. Besides new Zealand itself and some islands poking out. But for many millions of years there was more land, and as it sunk it brought nutrients that could support rich fishing grounds, but not low enough to make it very passable for major marine animals that couldn't go in shallow waters. Which could have made a very roomy and rich niche for something like a penguin. Until it sank even further down. And that is when dolphins and whales hit their stride in this region.
This is why I reddit
Abundance of food? Takes alot of calories for a gorilla sized penguin to roll
I was thinking along the lines of more oxygen in the air or something fundamental. Theres lots of food now.
This is the leading theory. Higher levels of oxygen and huge land masses free of human development to roam on.
It was always normal to have big animals we just killed most of them
Yeah we killed the giant penguin 60 million years ago.
I’m not talking about the giant penguin specifically. More large mammals than this have existed before and since
And less less than 1% of them were killed by humans.
More oxygen makes sense too
[removed]
[removed]
I think it was actually an abundance of carbon dioxide?
Carbon dioxide is plants. They used to be more huge too
The first trees would grow 100m straight up without branches. The earth was actually covered by fallen trees for millions of years before the bacteria that break them down evolved.
The Carboniferous period, names after the massive coal (carbon) deposits we discovered all around the world from those trees
let me throw in gigantism as an evolutionary trait that protects prey animals from predation, and thus escalation where predators needed to be larger to predate on huge prey.
the sheer variety of species back in time is massively scaled compared to today.
eventually things hit a critical mass though, as that size becomes unsupportable with slower reproduction and birthing cycles and strategies. look at pandas that would rather eat than mate, or alpha walrus social structure where most males never get a chance to copulate.
and so being smaller, caring for smaller young, requires much less resources, and allows much faster breeding, and so becomes evolution's dominant form.
add environmental changes like less oxygen, but count that as part of the resources a species needs to thrive, not a cause for gigantism.
human also put a negative pressure toward size. We shoot big animal as trophy, we compete for land with those animal. Land that used to feed large animal are now soybeans farm feeding us.
Trenbolone in the water.
[removed]
[removed]
Nothing, we just killed most of the species bigger than us when we evolved. Only ones we kept on purpose or ones that evolved alongside us in Africa were the main survivors.
At The Mountains of Madness
Yeah, but these don't seem albino. Although that could have been because the Elder Things had kept them cooped up in caverns. So it's likely we have finally found the evidence of one of the Elder Things' primary foodstuffs. And, I suppose, what they fed their protoplasmic slaves/pets. Tekeli-li!
Findings in title quoted from the linked summary^1 for a journal paper^2 identifying a penguin named in honour of paleontologist Ewan Fordyce.^3
From the linked summary:^1
>New Zealand has been a haven for earthbound birds for eons. The absence of terrestrial predators allowed flightless parrots, kiwis and moas to thrive. Now researchers are adding two prehistoric penguins to this grounded aviary.
>One species is a beefy behemoth that waddled along the New Zealand coastline nearly 60 million years ago. At almost 350 pounds, it weighed as much as an adult gorilla and is the heaviest penguin known to science.
>[The researchers] named the larger penguin Kumimanu (a mashup of the Maori words for “monster” and “bird”) fordycei and named the smaller penguin Petradyptes (“rock diver”) stonehousei.
>By creating 3D models of Kumimanu’s humongous humerus and comparing its size and shape with the flipper bones of prehistoric and modern penguins, the researchers estimate that the “monster bird” weighed a whopping [148.0 kg to 159.7 kg].
From the journal paper:^2
>Recent fossil discoveries from New Zealand have revealed a remarkably diverse assemblage of Paleocene stem group penguins.
>Here, we add to this growing record by describing nine new penguin specimens from the late Paleocene (upper Teurian local stage; 55.5–59.5 Ma) Moeraki Formation of the South Island, New Zealand.
>The largest specimen is assigned to a new species, Kumimanu fordycei n. sp., which may have been the largest penguin ever to have lived.
>Allometric regressions based on humerus length and humerus proximal width of extant penguins yield mean estimates of a live body mass in the range of 148.0 kg (95% CI: 132.5 kg–165.3 kg) and 159.7 kg (95% CI: 142.6 kg–178.8 kg), respectively, for Kumimanu fordycei.
From the University of Otago:^3
>The world’s largest penguin has been named in honour of Emeritus Professor Ewan Fordyce, recognising his enormous contributions to marine vertebrate paleontology.
>[Lead author] Dr Ksepka says he the researchers are “thrilled” to name one species after Emeritus Professor Fordyce in honour of his vast contributions to paleontology in general and to fossil penguins in particular.
^1 The biggest penguin that ever existed was a ‘monster bird’, Jack Tamisiea for the New York Times, 8 Feb. 2023, https://www.seattletimes.com/nation-world/the-biggest-penguin-that-ever-existed-was-a-monster-bird/
^2 Ksepka D., Field D., Heath T., Pett W., Thomas D., Giovanardi S., & Tennyson A. (2023). Largest-known fossil penguin provides insight into the early evolution of sphenisciform body size and flipper anatomy. Journal of Paleontology, 1-20. https://doi.org/10.1017/jpa.2022.88
^3 Paleontology powerhouse honoured by former students, University of Otago, 9 Feb. 2023, https://www.otago.ac.nz/social-impact-studio/news/otago0241045.html
Tomorrow's article: >Living remnants of prehistoric penguins found in Antarctic
Weekend article: >Strange obelisks and ruins located in Antarctic
Early next week: >Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn
This is some “At the Mountains of Madness”. What’s next? Shaggoths?
[removed]
Upon further consideration, a gigantic killer penguin would have been an excellent ending to a Monty Python sketch about "Scott, of the Antarctic"
Bring them back to life to play linebackers
350 lbs is pretty big for a linebacker, these guys would be better as OTs or maybe NTs
orcas probably got all their fat asses
Why were the ancient animals so large, initially?
most likely due to the greater concentration of oxygen in the atmosphere as well as an abundance of space// no environmental pressures to limit growth
I almost wonder if we could expect supersized intelligent life evolving on other worlds, but I guess it depends on atmospheric composition.
Based on studies from 2014, there was actually less oxygen in the atmosphere when dinosaurs were around
Humongous humerus... is he related to biggus dickus by any chance?
Dire Penguins rollout
Dire Penguins is the name of my tuxedo-attired Dire Straits tribute band.
I would go to that show.
Welcome to r/science! This is a heavily moderated subreddit in order to keep the discussion on science. However, we recognize that many people want to discuss how they feel the research relates to their own personal lives, so to give people a space to do that, personal anecdotes are allowed as responses to this comment. Any anecdotal comments elsewhere in the discussion will be removed and our normal comment rules apply to all other comments.
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.
[removed]
[removed]
[removed]
[removed]
[removed]
[removed]
The Mountain of Madness? Probably should stay away from there!
"prehistoric penguins’ humongous humerus"
Science brings us advanced tongue twisters.
bigwavedave000 t1_j7snwh6 wrote
I was always curious what made species gigantic in the past.