This is in response to a some comments made in a separate post in r/naturewasmetal and other commenters that commonly cite Gilbert, Ivany, and Uhen’s 2018 paper “Living Fast and Dying Young: Life History and Ecology of a Neogene Sperm Whale,” for why Orca-sized sperm whales were living common dolphin-like lifespans, and while I find the actual fossil evidence fascinating, I’m increasingly skeptical of the life-history and ecological conclusions drawn from it. To be clear, I’m not arguing that their GLG age estimates are necessarily wrong, nor am I arguing that megalodon didn’t prey on these whales. My issue is the leap from the ages represented at Lee Creek to the conclusion that these 10 m whales had a species-wide maximum lifespan of ~25 years, reached sexual maturity at only ~4–5 years, and evolved this extraordinarily fast life history primarily extreme predation pressure. Aka, the claim that Miocene Whales were insanely short-lived like Porpoises.
Gilbert et al. sectioned ten teeth and obtained ages ranging from 8 to 22 years. Using the relationship between tooth length and age, they then reconstructed ages for a larger sample and obtained a modal age at death of approximately 11 years, a mean of 12.4, and a predicted maximum around 23 years. The authors acknowledge that the distribution is artificially truncated at the young end because they deliberately excluded small teeth; however, they nevertheless interpret the absence of substantially older/larger specimens as evidence that these animals rarely lived beyond their early twenties (Gilbert, Ivany, and Uhen). Reading through the paper, the team assumes the animals represented at Lee Creek are sufficiently representative of the species as a whole for their age distribution to tell us about species-wide survivorship. Studies of living odontocetes demonstrate that this can be a dangerous assumption.
Suydam’s 2009 dissertation on eastern Chukchi Sea belugas is particularly relevant. His biological sample consisted of harvested whales, but comparison with aerial observations demonstrated that the harvested animals were not representative of the entire population. Larger, whiter animals were overrepresented and smaller, darker animals underrepresented. Suydam specifically attributes sampling differences partly to age/sex segregation and warns that results from biological sampling should be qualified before being extrapolated to the larger population. Satellite tracking also demonstrated demographic differences in habitat use: females and younger whales tended to remain around the shelf break, whereas some large males traveled far north into deep, ice-covered waters (Suydam 17–20). In other words, even in a living species where we can observe the animals directly, a sample collected in one place can give a distorted picture of the population because different ages and sexes don't distribute themselves randomly.
Cockcroft and Ross found essentially the same problem in South African bottlenose dolphins. Different demographic classes occupied different habitats: females with calves were concentrated nearshore, adolescents occurred farther offshore, and adult males and resting females fed farther offshore still. Consequently, the shark-net mortality sample was strongly biased toward particular demographic classes. The authors explicitly caution against straightforward demographic interpretation of such a sample (Cockcroft and Ross). If we only had the remains generated by one of those habitats millions of years later, we could potentially mistake an ecologically selected subset of the population for the species’ actual mortality distribution.
Pilot whales provide another useful comparison. Kasuya, Sergeant, and Tanaka’s study of hundreds of long-finned pilot whales shows pronounced age- and sex-related demographic structure and substantially greater longevity than the Lee Creek reconstruction. More generally, odontocetes frequently change social associations and distributions as they mature. That raises an obvious alternative explanation for a fossil locality dominated by roughly 8–22-year-old animals with a mode around 11**;** perhaps Lee Creek disproportionately sampled a particular demographic class of adolescents or young adults rather than recording the survivorship curve of the entire species (Kasuya, Sergeant, and Tanaka).
This doesn't prove Lee Creek was a bachelor-group habitat or stranding location, because don't have enough evidence to establish that. HOWEVER, that's precisely the problem: Gilbert et al. cannot determine the sex, reproductive status, social group, or migration pattern of an animal from these isolated teeth. If an odontocete population was segregated by age and sex, as many living odontocetes are, then “the oldest animal represented at this locality was ~22” is not necessarily equivalent to “members of this species rarely lived beyond ~22.”
The comparative life-history argument makes me even more skeptical of the stronger interpretation. Gilbert et al. emphasize the contrast with modern sperm whales and killer whales, which mature slowly and can live for many decades. But Physeter and Orcinus themselves have unusually slow life histories among odontocetes. There's a large middle ground represented by animals such as belugas, pilot whales, and bottlenose dolphins. These animals mature considerably earlier than modern sperm whales while nevertheless retaining potential lifespans measured in several decades.
Reading through these papers, they don't look much like the proposed Lee Creek trajectory. Suydam estimated 50% female sexual maturity in eastern Chukchi belugas at about 8.25 years, with average age at first birth around 8.27 years (Suydam). Cockcroft and Ross found female bottlenose dolphins reaching sexual maturity at approximately 9–11 years, with males later, while multiple whales were found to survive beyond 40 years (Cockcroft and Ross). Pilot whales likewise combine multi-year juvenile development with potential lifespans of several decades.
This matters because Gilbert et al. aren't proposing merely that the Lee Creek physeteroid had a faster life history than an orca. They reconstruct an orca-sized animal (~8–10 m) reaching sexual maturity at only ~4–5 years and rarely surviving beyond 25. That is an extraordinarily fast life-history regime for an odontocete of that size and something the authors acknowledge when they describe its inferred rate of attainment of adult body size as unprecedented among similarly sized living taxa.
But here's the problem: even the ~4–5-year maturity estimate is not an independent observation. Gilbert and the team wrote that large odontocetes tend to reach sexual maturity at approximately 20% of maximum lifespan and reason that, given a lifespan of ~25 years, the Lee Creek animal could have begun reproducing at that 4-5 year mark. They also use estimated size at maturity and a von Bertalanffy model, but no fossil independently demonstrates that a four- or five-year-old animal was reproductively mature. Therefore, the supposedly early maturity is partly dependent upon the inferred very short lifespan; it isn't a separate piece of evidence independently confirming it.
That brings me to Otodus. Again, it's pretty clear based on their size, the fossil record, and modern ecological analogues that the shark likely preyed upon these animals when the opportunity arose. An 8–10 m odontocete would certainly have been vulnerable when young, and a physically mature O. megalodon was more than large enough to take down large individuals while bigger Physeteroids may have represented another source of predation.
But the hypothesis requires considerably more than “Otodus ate these whales.” To explain the reconstructed life history, predation would seemingly have to impose such enormous and persistent extrinsic mortality that natural selection compressed the life-history schedule of an ~8–10 m odontocete toward something much more reminiscent of small, fast-lived cetaceans such as porpoises. That is an extraordinary ecological proposition.
As I mentioned earlier, extant belugas, pilot whales, and bottlenose dolphins all experience natural mortality and predation. Yet they retain substantially later maturation and multi-decadal potential longevity. As the Lee Creek physeteroid grew toward 7–10 m, it would itself have become an enormous macropredatory cetacean, progressively reducing the number of predators capable of killing it. Gilbert et al. actually invoke rapid growth toward a size refuge from predation. That makes rapid juvenile growth as an adaptation to megalodon predation quite plausible, but it does not independently demonstrate the extreme species-wide mortality required to explain why essentially no individuals supposedly survived beyond their twenties.
So I think there are several propositions here that need to be separated.
The teeth really can belong to animals that died at 8–22 years old.
Otodus megalodon preyed on these whales.
The species had a faster life history than modern sperm whales and killer whales.
However, none of those propositions necessarily entails:
“This ~8–10 m odontocete matured at 4–5, almost never lived past 25, and evolved this porpoise-like life-history tempo because megalodon predation was unimaginably intense.”
A more conservative possibility is that the species had something closer to an ordinary medium-to-large odontocete life history with earlier maturation than modern sperm whales/orcas and perhaps substantial predation mortality, but still potential longevity of several decades. Lee Creek could've disproportionately sampled adolescents and young adults because of social organization, habitat use, migration, or some other demographic filter.
I don't think the available evidence proves that alternative either. My point is that both scenarios can potentially generate the fossil observations. The living odontocete literature shows us that locality-specific samples can be heavily structured by age, sex, reproductive condition, and habitat use. Without independent evidence about those variables in the Lee Creek physeteroid, I don't think the fossil age distribution alone establishes the extraordinary life-history regime that Gilbert et al. propose.
In other words, I find “these Lee Creek whales died surprisingly young” convincing. I find “therefore the entire species had a ~25-year maximum lifespan, matured at ~4–5, and evolved this unprecedented life history primarily because of extreme megalodon predation” much more speculative.
If you want to respond to disagree and point out something in the paper that I didn't see, please feel free to respond.
Works Cited
Cockcroft, V. G., and G. J. B. Ross. “Age, Growth, and Reproduction of Bottlenose Dolphins Tursiops truncatus from the East Coast of Southern Africa.” Fishery Bulletin, vol. 88, 1990, pp. 289–302.
Gilbert, K. N., L. C. Ivany, and M. D. Uhen. “Living Fast and Dying Young: Life History and Ecology of a Neogene Sperm Whale.” Journal of Vertebrate Paleontology, vol. 38, no. 2, 2018, e1439038.
Kasuya, Toshio, David E. Sergeant, and Katsuhiko Tanaka. “Re-examination of Life History Parameters of Long-finned Pilot Whales in the Newfoundland Waters.” Scientific Reports of the Whales Research Institute, no. 39, 1988, pp. 103–119.
Suydam, Robert Scott. Age, Growth, Reproduction, and Movements of Beluga Whales (Delphinapterus leucas) from the Eastern Chukchi Sea. PhD dissertation, University of Washington, 2009.
I've noticed this compared to Korean, Chinese, Japanese, or especially Indian-Americans, Filipino-Americans seem to largely be absent from politics or the corporate hierarchy despite being one of the largest asian ethnic groups in the US.
Why is that?
I've been thinking of how places like Hong Kong have a mean annual temp of 23.5 centigrade and have largely sweltering weather and nonexistent snow, yet because it has winters below 18 centigrade, it's not considered to be tropical like places such as the Bahamas or Goa.
Is there that big of a difference between Cwa and Aw climates?
It's a strange thing to ask, but when you compare Filipinos to other cosmopolitan diasporas like Chinese enclaves, the Jewish diaspora, the Indian diaspora, Lebanese, Irish, Italians, and others that are generally global and have achieved massive success in terms of being represented in CxO positions, financial institutions, and politics, Filipinos are basically absent from these positions globally, almost disproportionately represented by caretakers & nurses.
Why is this?
We're one of the top 3 largest Asian-American groups in the country but have ZERO representation in the House or Senate, Indian-American & Chinese-American students outnumber Fil-ams in places like Berkeley 4-to-1, we've made no in-roads into building our own firms, lobbying organizations, banks, startups, etc.
It's very frustrating because it seems like so many other ethnic groups like Jewish-Americans, the Irish, the Italians, and others we've made relatively little progress outside of appearing in animated movies and are still overwhelmingly associated with being "nice" or working as "nurses".
I mean, compare it to another English-speaking country with a direct colonial history relationship to an asian nation, the UK & India. Rishi Sunak managed to become PM, Indian-Brits are now the largest property owning group in LONDON, and have 45 MPs in the UK Parliament.
I get that it shouldn't matter that much in the long-run, but part of me feel like building that power does matter. We keep being perceived as "easy to work with" and "non-complaining" and that seems like an excuse for US companies to potentially exploit us. Without the mobilized lobbying power, our needs are gonna be ignored. If we don't build the power to define our interests, I'm worried that other groups will define them for us.
Is this cultural or economic? What keeps driving this underperformance?
I've seen a few people on here point out that even someone like the Sandy Hill Pittman woman who survived the 1996 Everest expedition had actually had more climbing experience than implied by Krakauer, though I'm not certain how true this statement is.
To the people who've been on the camps or at least have done their fair share of research on the mountain and its tourism industry, how true are the negative stereotypes of modern Everest climbers and if they're not, are they primarily just fellow "peakbaggers" who shelled out an ungodly amount of money to reach the top?
It seems like it's essentially illegal now for someone to attempt what Kurtyka or Messner did with pair ascents, if they have a guide, wouldn't that guide automatically shift them towards doing a more conventional route instead, how is alpine mountaineering in Nepal supposed to work now?
I asked this on another sub, but it was a bit smaller so I was curious if anyone here who's into mountain climbing has seen similar problems to those described on Everest.
If you've been on other 8000ers is the lines, & trash a problem on mountains like Dhaulagiri, Kangchenjunga, or Makalu?
In the US is this a common issue on the 4000ers and the Alaskan peaks like Denali?
In South America, what about peaks like Aconcagua or Huascaran?
etc.
I'm generally very curious about this area as these summits have generally received a lot more mountaineering attention than other 7000ers compared to say, the Nepalese or Pakistani 7000ers simply due to their locations in the Former Soviet Union and how institutionalized mountaineering was as a sport in that part of the world.
How difficult were these climbs? I understand that Peak Pobeda's notoriously known for being very hard, but how does it stack up to something like K2, furthermore, how difficult are the other peaks(barring Lenin) and because of their relative popularity, how extensive is the infrastructure and fixed line support here compared to other peaks in High Asia?
Like, I get that it's isolated, but the Gasherbrum peaks, Distaghil Sar, Baintha Brakk, and others have defined names while all being pretty far away from Balti villages too.
I know that there's the alternate name, Mt. Godwin-Austen, but that name's rarely used unlike Everest.
For some context, the Mahalangur Himal is the region of the Himalayas where Everest is.
Here, even the lowest 8000er, Cho Oyu is still a tad higher up than the twin 8000ers over the Kali Gandaki while Makalu & Lhotse are already the 5th and 4th highest summits on Earth, with Makalu already being over 300m higher up than Dhaulagiri or Manaslu.
Even compared to the Karakoram, the lower 8000ers here are noticeably higher up than all the Gasherbrum peaks & Nanga Parbat.
What drives this region to specifically be filled with such high peaks, even when compared to other areas in the Himalayas?
I'm referring to peaks like Kangchenjunga, Dhaulagiri, Manaslu, Annapurna, etc. how extensive is the Sherpa support, commercialization, and more morbidly, the trash and bodies compare on these mountains to Everest?
Despite Kilimanjaro being just as high up, approximately 6km, the mountain has considerably less snow cover when compared to Cotopaxi, Chimborazo, or Cayambe.
What are some reasons for this, my guess is the Amazon Rainforest having way more moisture than the Serengeti, but if there's more to it, let me know.
Like in terms of Sherpa support, base village amenities, crowds, & tourist environment how do places like Dhaulagiri, Manaslu, Cho Oyu, Kangchenjunga and Annapurna compare to what we see in Everest?
I know that it's relatively common to hear a talking point that Mount Everest is overrun by tourists, trash, and strong measures have been made on the part of climbing companies and their staff to make the climb way more "civilized" and easier (aka ladders on the icefall, extensive guided ropes, Sherpa assistance at every corner).
But I'm curious, how does this stack up to other mountains in your experience? Is the situation worse or comparable in places in the Andes like Aconcagua or Huascaran? How about Rainier & Denali back in the States or other 8000ers like Nanga Parbat & Dhaulagiri?
Even when looking outside of the Himalayas & Karakoram, other peaks & Central & South Asia like Jengish Chokusu, Kongur Tagh, & Tirich Mir are each 472, 688, and 747m. HIGHER up than Aconcagua, the highest peak in the Andes and the highest peak outside of Asia.
What drives the fact that there are so many mountains that are so much higher up in altitude than the Andes and other tropical/subtropical mountain ranges?
An interesting peculiarity I've noticed in the Philippines is that when you compare the weather of Northern Luzon to Central & Northern Vietnam and Southern China, the Philippines pretty much never experiences milder winters when compared to Indochina & China at similar latitudes
For instance, the City of Laoag, for example, has a mean January temp of roughly 25.2 Celsius while Tuguegarao has a mean temp of 23.6 Celsius. For comparison, Haiphong & Hanoi's mean January temperatures are roughly 16.3 & 16.5 Celsius, while Haikou & Sanya's mean January temperatures are 18.2 & 22.3 centigrade, respectively.
What peculiarities in the Philippines geography prevent a Cwa climate from happening in the Northern Islands?
