Body size and metabolic rate are intertwined, a factor that is especially important to understand with regard to animals that live in aquatic environments, where heat loss is related to water temperature. Payne et al. developed a method to estimate routine metabolic rate based on measures from tagged fish, and combined the estimates with published respirometry rates to create a dataset spanning the entire body size range of extant fishes. Using these data, the authors found a scaling imbalance between heat production and loss that affects especially large, mesothermic fishes in warm waters. This imbalance both explains the distribution of these fish in cooler waters and suggests a special sensitivity to warming waters. —Sacha Vignieri
---
Abstract:
Body size and temperature set metabolic rates and the pace of life, yet our understanding of the energetics of large fishes is uncertain, especially of warm-bodied mesotherms, which can heavily influence marine food webs. We developed an approach to estimate metabolic heat production in fishes, revealing how routine energy expenditure scales with size and temperature from 1-milligram larvae up to 3-tonne megaplanktivorous sharks. We found that mesotherms use approximately four times more energy than ectotherms use and identified a scaling mismatch in which rates of heat production increase faster than heat loss as body size increases, with larger fish becoming increasingly warm bodied. This scaling imbalance creates an overheating predicament for large mesotherms, helping to explain their cooler biogeographies. Contemporary mesotherms face high fuel demands and overheating risks, which is a concern given their disproportionate demise during prior climate shifts.
No, because most of the estimates are wonky as hell. For one, calories from silage don't exactly translate directly to calories humans can make use of. Second, most estimates are worst case only and ignore the fact most animals are pastured for some/all of the year on marginal land. Some animals can survive entirely on foraging and waste from agriculture (pigs are a great example).
On the other side, not all climates can produce all the plants required for a balanced vegan diet. Here in Canada, nothing grows for 6 months and what does grow is relatively limited.
The lowest energy system would likely include a reduction in animal products but not a complete elimination, while keeping transportation to a minimum.
Also, just like with energy generation, there's the game theory aspect. If you reduce emissions, will everyone cooperate? What if you suffer only to have someone else increase their emissions anyway? We see this here... We limit our fisheries to try preserve ocean fish, only for Chinese vessels to sit on the edge of our borders hoovering up all the aquatic life...
Animals or humans don't cause any net emissions, because the same carbon was captured from the atmosphere in the first place. No new carbon is added. Also, the same amount of methane is broken down in the atmosphere as is created. Increasing co2 is only possible by burning fossil fuels.
Donald Trump has probably done more to halt CO2 production than any other president, by extending the COVID pandemic and closing the Straight of Hormuz.
I want to ignore these articles as it is so painful to watch the beautiful clockwork of the natural world unravel. I hate facing the suffering, diminishment, and extinction of so much in the name of profiteering and ever-increasing growth.
But this is the world now, there will only be more stories like this, and so I'm not turning away from it any further. The world becomes less beautiful, less rich, less full every year.
I do volunteer, donate, and advocate and I won't use my extreme pessimism as an excuse not to engage. But in private, I mourn what is coming with little hope for substantial reduction in harm. If anything, those with power seem upset that we're not doing more to fasttrack catastrophe - if it's going to happen, may as well be the one to profit from it as much as possible before you're dead, the thinking seems to go.
It's hard when your job and even hobbies are intertwined with this destruction. I enjoy working with computers and industrial machinery - two giant sources of pollution and social disruption. I sometimes feel this existential crisis where I am part of the problem yet I have no way to escape and become filled with guilt. Yet without this technology our lives would be more difficult.
I sometimes think about a post-industrial fantasy world where technology still exists, though minimally, and carefully applied to solve real problems humanity faces instead of selling FOMO or millions of "shiny things" that wind up in land fills so you can sell the new FOMO/shinything so some numbers on a spread sheet goes up.
Serious questions, how is this destruction and not just "change?" It seems throughout time the world has experienced acute shifts, dying offs and other events. In those transition periods many animals that you know and love today finally got a shot at main character roles. Heck the reduction of o2 in the air that killed/shrunk a lot of dinosaurs is basically the opening slave for you to be able to write this Hacker News comment.
None of this is to say don't mourn or long for any of this, but the show doesnt end, the charecters just change.
First off, I'm vegetarian and generally climate-conscious. I think we humans should do what we can in order to protect our planet. I think we can do a lot to keep the planet a good place for all living beings.
But to also say something unpopular, humans are part of the natural world. So these human driven changes to nature are just 'nature changing nature'. I understand that we are potentially causing mass extinctions, but this needs to be seen as natural unless you take for granted that humans are inherently 'special' which leads to speciesism. So, this might just be the way planets with intelligent species evolve, they outcompete the others and exploit natural resources to their benefit. It might just be a biological/evolutionary law.
Also, to be fair, _most_ of life on earth will survive this. Bacteria outnumber all other class of organisms IIRC, and they are shown to survive in truly challenging conditions.
There was a Norwegian TV series called Catastrophe or something to educate the whole family about how insecure and bad the future is. What to do if a Russian van keeps driving through your neighorhood. What to do in a natural catastrophe.
How nice. Us adults who have ruined the planet[1][2] and now we are lecturing the youngins about how to deal with this suckage.
With a bizarrely cherry narration. Did you know things are about to suck for you? Just your usual shameless state TV programming.
But we, with our particular national programming, are just supposed to act like we were just spoiled brats that now have to live without dessert post-dinner. The “dessert generation” indeed.
[1] Um akshually, we haven’t ruined the planet—the planet is just minerals! It doesn’t care. We are just ruining the foundation for our own comfortable exi— yeah no kidding.
> I do volunteer, donate, and advocate and I won't use my extreme pessimism as an excuse not to engage.
I think it is ok to not engage. The idea that you can impact the world is largely an artifact of modernity. In reality, capital is more than happy to let you take the blame for its own suicidal tendencies.
Is that sharks are an ancient species and they’ve survived way warmer oceans even relatively recently.
For example the Medieval Warm Period Sargasso Sea surface temperatures were 1°C warmer than 400 years ago, and Pacific Ocean water temperatures were 0.65°C warmer than the decades before.
Sharks are an ancient division of life, roughly 440 million years old, which has survived far warmer oceans.
There are ~500 living species of shark and likely tens of thousands extinct in their lineage.
We are perpetrating a mass extinction event that incorporates not just temperatures, but ocean acidification and trophic cascade for fisheries. In mass extinctions, enough things about the ecosystem change that specialists often go extinct. Great White Sharks are a specialist species in their extreme size; Most size specialists are in a precarious local maxima that disappears too quickly to adapt if conditions change drastically.
I presume it was due to the temperature gradient being extremely low, so they could gradually adapt to the change over hundreds of years. We're pulling the handbrake in geological terms.
(that chart was made in 2016, given that we were at +1.5C last year we're outdone even the most pessimistic scenario presented on that graph by quite a bit, the line is now almost horizontal)
The warmer ocean thing seems to be blanketing over the real issue: we are overfishing.
Which is really heartening to me, because decreasing the temperature of the ocean seems daunting, but not dragging giant nets through the ocean nonstop seems pretty straightforward.
This might be the worst idea I've ever seen. I'm glad they are so interested in reducing the effects of global warming - that's fantastic - but they are literally purposefully releasing a toxic, major air pollutant into the air to create in their own words "clouds of dust" for the purposes of reflecting sunlight. Sure, there might be a slight cooling effect but who in their right mind could possibly think this is a good idea?!
I understand they are deploying to the stratosphere and not the troposphere but I can't imagine there aren't any negative second-order effects.
As someone who lives in a city with a major PM2.5 problem that effects the millions here on the daily (near an active stratovolcano no less!), reading about what they are doing was somewhat infuriating.
I agree. I see climate engineering as the short term solution that will get us to the long term solution. Without commenting on this specific implementation, experiments could be done. Many of the aerosol-type ideas are not permanent and would not last (and neither would their impacts). Models are good enough to understand the impacts and if they are not now they can be improved through a cycle of experimentation and further modeling. Other solutions are decades away and they have been for decades. Time to take this seriously. We are already engineering the climate, just not one conducive to life.
It’s a white noise so hard to notice, but our behavior is fundamentally driven by the design of our nervous system. Thus the more immediate the consequence, the better we link our behavior and can adjust. Since this is true at an individual level, the dynamic emerges from societies and populations as well, even large ones.
For example, something is red, you touch it, get burned. You won’t touch it again.
Environmental harm unfortunately is precisely the opposite. Consequences arise on a very long arc, in some cases beyond even our lifetimes. We register problems like this only intellectually, and even that becomes clouded with politics.
So the problem is kind of inevitable unfortunately.
They will move to different locations like they always have been for the past 400 million years. Sharks are older than trees, they can adapt to climate change better than anything alive right now.
As sad as these things are... one needs to also accept, that as capable as we are of changing our environments, from transportation, to air conditioning, we do not control all the things. We have and continue to over-fish in a lot of places, and I have deep concerns over farmed fish and the impact of less than natural foods on our own health.
A lot of the changes to the waters is well outside human control... there's a huge balance of factors at play from the earth, moon and sun. We don't control these things... and to what impact we can/do, I'm not sure that anything we might do may not have unintended consequences that are materially worse.
We can definitely do some things, but the level of internalized and externalized guilt that people in and outside these discussions seem to carry and put on others isn't at all healthy in and of itself.
34 comments
[ 5.0 ms ] story [ 71.9 ms ] threadpaper link: https://www.science.org/doi/10.1126/science.adt2981
---
Editor Summary:
Body size and metabolic rate are intertwined, a factor that is especially important to understand with regard to animals that live in aquatic environments, where heat loss is related to water temperature. Payne et al. developed a method to estimate routine metabolic rate based on measures from tagged fish, and combined the estimates with published respirometry rates to create a dataset spanning the entire body size range of extant fishes. Using these data, the authors found a scaling imbalance between heat production and loss that affects especially large, mesothermic fishes in warm waters. This imbalance both explains the distribution of these fish in cooler waters and suggests a special sensitivity to warming waters. —Sacha Vignieri
---
Abstract:
Body size and temperature set metabolic rates and the pace of life, yet our understanding of the energetics of large fishes is uncertain, especially of warm-bodied mesotherms, which can heavily influence marine food webs. We developed an approach to estimate metabolic heat production in fishes, revealing how routine energy expenditure scales with size and temperature from 1-milligram larvae up to 3-tonne megaplanktivorous sharks. We found that mesotherms use approximately four times more energy than ectotherms use and identified a scaling mismatch in which rates of heat production increase faster than heat loss as body size increases, with larger fish becoming increasingly warm bodied. This scaling imbalance creates an overheating predicament for large mesotherms, helping to explain their cooler biogeographies. Contemporary mesotherms face high fuel demands and overheating risks, which is a concern given their disproportionate demise during prior climate shifts.
- if everyone on the entire planet went 100% vegan from tomorrow, will carbon emissions really go down by 60%?
On the other side, not all climates can produce all the plants required for a balanced vegan diet. Here in Canada, nothing grows for 6 months and what does grow is relatively limited.
The lowest energy system would likely include a reduction in animal products but not a complete elimination, while keeping transportation to a minimum.
Also, just like with energy generation, there's the game theory aspect. If you reduce emissions, will everyone cooperate? What if you suffer only to have someone else increase their emissions anyway? We see this here... We limit our fisheries to try preserve ocean fish, only for Chinese vessels to sit on the edge of our borders hoovering up all the aquatic life...
But this is the world now, there will only be more stories like this, and so I'm not turning away from it any further. The world becomes less beautiful, less rich, less full every year.
I do volunteer, donate, and advocate and I won't use my extreme pessimism as an excuse not to engage. But in private, I mourn what is coming with little hope for substantial reduction in harm. If anything, those with power seem upset that we're not doing more to fasttrack catastrophe - if it's going to happen, may as well be the one to profit from it as much as possible before you're dead, the thinking seems to go.
I sometimes think about a post-industrial fantasy world where technology still exists, though minimally, and carefully applied to solve real problems humanity faces instead of selling FOMO or millions of "shiny things" that wind up in land fills so you can sell the new FOMO/shinything so some numbers on a spread sheet goes up.
None of this is to say don't mourn or long for any of this, but the show doesnt end, the charecters just change.
But to also say something unpopular, humans are part of the natural world. So these human driven changes to nature are just 'nature changing nature'. I understand that we are potentially causing mass extinctions, but this needs to be seen as natural unless you take for granted that humans are inherently 'special' which leads to speciesism. So, this might just be the way planets with intelligent species evolve, they outcompete the others and exploit natural resources to their benefit. It might just be a biological/evolutionary law.
Also, to be fair, _most_ of life on earth will survive this. Bacteria outnumber all other class of organisms IIRC, and they are shown to survive in truly challenging conditions.
How nice. Us adults who have ruined the planet[1][2] and now we are lecturing the youngins about how to deal with this suckage.
With a bizarrely cherry narration. Did you know things are about to suck for you? Just your usual shameless state TV programming.
But we, with our particular national programming, are just supposed to act like we were just spoiled brats that now have to live without dessert post-dinner. The “dessert generation” indeed.
[1] Um akshually, we haven’t ruined the planet—the planet is just minerals! It doesn’t care. We are just ruining the foundation for our own comfortable exi— yeah no kidding.
[2] Like with Norwegian oil/gas extraction
There will be a shark in someones mind in a 100 years time - if its not a real one, let it be the one you shared with your mind, here and now.
I think it is ok to not engage. The idea that you can impact the world is largely an artifact of modernity. In reality, capital is more than happy to let you take the blame for its own suicidal tendencies.
Is that sharks are an ancient species and they’ve survived way warmer oceans even relatively recently.
For example the Medieval Warm Period Sargasso Sea surface temperatures were 1°C warmer than 400 years ago, and Pacific Ocean water temperatures were 0.65°C warmer than the decades before.
There are ~500 living species of shark and likely tens of thousands extinct in their lineage.
We are perpetrating a mass extinction event that incorporates not just temperatures, but ocean acidification and trophic cascade for fisheries. In mass extinctions, enough things about the ecosystem change that specialists often go extinct. Great White Sharks are a specialist species in their extreme size; Most size specialists are in a precarious local maxima that disappears too quickly to adapt if conditions change drastically.
https://xkcd.com/1732
(that chart was made in 2016, given that we were at +1.5C last year we're outdone even the most pessimistic scenario presented on that graph by quite a bit, the line is now almost horizontal)
For a shark lover, you should know that shark is not a species, but a taxonomy group.
From there, everything else you assume is incorrect (ie: some species of sharks have definitely gone extinct)
Which is really heartening to me, because decreasing the temperature of the ocean seems daunting, but not dragging giant nets through the ocean nonstop seems pretty straightforward.
I don’t see a way out except for stratospheric aerosol injection.
I understand they are deploying to the stratosphere and not the troposphere but I can't imagine there aren't any negative second-order effects.
As someone who lives in a city with a major PM2.5 problem that effects the millions here on the daily (near an active stratovolcano no less!), reading about what they are doing was somewhat infuriating.
For example, something is red, you touch it, get burned. You won’t touch it again.
Environmental harm unfortunately is precisely the opposite. Consequences arise on a very long arc, in some cases beyond even our lifetimes. We register problems like this only intellectually, and even that becomes clouded with politics.
So the problem is kind of inevitable unfortunately.
They will move to different locations like they always have been for the past 400 million years. Sharks are older than trees, they can adapt to climate change better than anything alive right now.
A lot of the changes to the waters is well outside human control... there's a huge balance of factors at play from the earth, moon and sun. We don't control these things... and to what impact we can/do, I'm not sure that anything we might do may not have unintended consequences that are materially worse.
We can definitely do some things, but the level of internalized and externalized guilt that people in and outside these discussions seem to carry and put on others isn't at all healthy in and of itself.