Can anyone describe the anatomy of Perucetus colossus, just published in Nature, a middle Eocene whale claimed to be bigger than a blue whale? An artist's conception shows it with a forelimb apparently with free
digits, being used to support the body above the sea floor.
On 8/2/23 9:34 PM, John Harshman wrote:
Can anyone describe the anatomy of Perucetus colossus, just published in Nature, a middle Eocene whale claimed to be bigger than a blue whale? An artist's conception shows it with a forelimb apparently with freeStill can't see the article, but the public bits do include hints that
digits, being used to support the body above the sea floor.
the only actual material includes only vertebrae and ribs, and the rest
of the skeleton is reconstructed based on presumed relatives. The tail
is even based on extant manatees. So, a bit of press release hype.
On Friday, August 4, 2023 at 9:27:02 AM UTC-7, John Harshman wrote:FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.com
On 8/2/23 9:34 PM, John Harshman wrote:
Can anyone describe the anatomy of Perucetus colossus, just published in >>> Nature, a middle Eocene whale claimed to be bigger than a blue whale? An >>> artist's conception shows it with a forelimb apparently with freeStill can't see the article, but the public bits do include hints that
digits, being used to support the body above the sea floor.
the only actual material includes only vertebrae and ribs, and the rest
of the skeleton is reconstructed based on presumed relatives. The tail
is even based on extant manatees. So, a bit of press release hype.
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
The fossil is of some ribs and backbone, and they're extremely big and heavy. No evidence for what the skull or limbs were like, so body mass estimates are just that: estimates. It may likely be as big as a blue whate, or at least comparable. Newssources really went to town.
On 8/4/23 12:49 PM, erik simpson wrote:FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.com
On Friday, August 4, 2023 at 9:27:02 AM UTC-7, John Harshman wrote:
On 8/2/23 9:34 PM, John Harshman wrote:
Can anyone describe the anatomy of Perucetus colossus, just published in >>> Nature, a middle Eocene whale claimed to be bigger than a blue whale? An >>> artist's conception shows it with a forelimb apparently with freeStill can't see the article, but the public bits do include hints that
digits, being used to support the body above the sea floor.
the only actual material includes only vertebrae and ribs, and the rest >> of the skeleton is reconstructed based on presumed relatives. The tail
is even based on extant manatees. So, a bit of press release hype.
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
sources really went to town.The fossil is of some ribs and backbone, and they're extremely big and heavy. No evidence for what the skull or limbs were like, so body mass estimates are just that: estimates. It may likely be as big as a blue whate, or at least comparable. News
You don't get into Nature without hype.
On Friday, August 4, 2023 at 9:27:02 AM UTC-7, John Harshman wrote:ever seeing.
On 8/2/23 9:34 PM, John Harshman started his first on-topic thread to s.b.p. that I recall
Can anyone describe the anatomy of Perucetus colossus, just published in Nature, a middle Eocene whale claimed to be bigger than a blue whale? An artist's conception shows it with a forelimb apparently with free digits, being used to support the body above the sea floor.
Still can't see the article, but the public bits do include hints that
the only actual material includes only vertebrae and ribs, and the rest
of the skeleton is reconstructed based on presumed relatives. The tail
is even based on extant manatees.
So, a bit of press release hype.FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.com
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
The fossil is of some ribs and backbone, and they're extremely big and heavy. No evidence for what the skull or limbs were like, so body mass estimates are just that: estimates. It may likely be as big as a blue whate, or at least comparable. Newssources really went to town.
On 8/2/23 9:34 PM, John Harshman wrote:
Can anyone describe the anatomy of Perucetus colossus, just published
in Nature, a middle Eocene whale claimed to be bigger than a blue
whale? An artist's conception shows it with a forelimb apparently with
free digits, being used to support the body above the sea floor.
Still can't see the article, but the public bits do include hints that
the only actual material includes only vertebrae and ribs, and the rest
of the skeleton is reconstructed based on presumed relatives. The tail
is even based on extant manatees. So, a bit of press release hype.
On 8/4/23 09:26, John Harshman wrote:
On 8/2/23 9:34 PM, John Harshman wrote:
Can anyone describe the anatomy of Perucetus colossus, just published
in Nature, a middle Eocene whale claimed to be bigger than a blue
whale? An artist's conception shows it with a forelimb apparently
with free digits, being used to support the body above the sea floor.
Still can't see the article, but the public bits do include hints that
the only actual material includes only vertebrae and ribs, and the
rest of the skeleton is reconstructed based on presumed relatives. The
tail is even based on extant manatees. So, a bit of press release hype.
I get the idea that this guy might have been so old that
it might not have echolated a target like the modern grey
whale before diving.
Maybe it could just hold its breath for a longer period of
time?
what would be cool is if you could find something on the
formation of sonar among the cetaceans in general. Please
post if you could find something.
On 8/7/23 9:53 AM, Peter Nyikos wrote:
On Friday, August 4, 2023 at 3:49:17 PM UTC-4, erik simpson wrote:
On Friday, August 4, 2023 at 9:27:02 AM UTC-7, John Harshman wrote:ever seeing.
On 8/2/23 9:34 PM, John Harshman started his first on-topic thread to s.b.p. that I recall
Can anyone describe the anatomy of Perucetus colossus, just published in
Nature, a middle Eocene whale claimed to be bigger than a blue whale? An
artist's conception shows it with a forelimb apparently with free
digits, being used to support the body above the sea floor.
The artist's conception in the article does not show the digits to be free: the
body outline includes them.
We must be looking at different artist's conceptions. The one I'm
looking at is not in the Nature article.
This one:
https://www.cnn.com/2023/08/02/world/ancient-colossal-whale-perucetus-colossus-scn/index.html
Still can't see the article, but the public bits do include hints that >>> the only actual material includes only vertebrae and ribs, and the rest >>> of the skeleton is reconstructed based on presumed relatives. The tail >>> is even based on extant manatees.
There is a tiny notch in the middle in Fig. 2. of the linked article below.
Note that the tail is entirely conjectural.
The actual material consists
of some thoracic vertebrae, a few ribs, and a piece of the pelvis.
Strangely enough, a web search for "manatee tail" gave less than 5% photographs
showing a complete tail. Yet it is the quickest and easiest way to tell a manatee from a dugong.
FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.comSo, a bit of press release hype.
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
sources really went to town.First, I got a column of tiny reproductions of the pages that I was unable to magnify.
However, clicking a seemingly dead view-page button, I got a great webpage showing the article
and a note that I have access through the University of South Carolina library system.
The fossil is of some ribs and backbone, and they're extremely big and heavy. No evidence for what the skull or limbs were like, so body mass estimates are just that: estimates. It may likely be as big as a blue whate, or at least comparable. News
by additional deposition of bone on their external surface5 (that is, pachyostosis sensu stricto). BMI is documented in cetaceans’ amphibious close relatives11, as well as early members of the clade, the basilosaurids in particular.The artist's conception on Fig. 2 makes it out to be substantially smaller, in the usual sense,
than the blue whale on the same illustration. However, where weight is concerned,
the abstract says,
"We use the skeletal fraction to estimate the body mass of P. colossus, which proves to be a contender for the title of heaviest animal on record."
In fact, the article seems to emphasize a condition that a certain insufferable self-advertiser
in s.b.p. and t.o. has advanced for a "waterside hypothesis" for proximal ancestors of *Homo*: pachyostosis.
"The adaptations of shallow-diving, slow-swimming species often comprise bone mass increase (BMI). This is produced by the infilling of the inner cavities of skeletal elements with compact bone (that is, osteosclerosis) and, in the more extreme cases,
they acquired large sizes (up to around 20 m in body length3) and BMI. The degree of their BMI nevertheless did not match, up until now, that of some sirenians, for example, of which the whole rib cage is both strongly osteosclerotic and pachyostotic ["Extant cetaceans have conversely acquired an entirely different bone microanatomy, with an osteoporotic-like structure typical of pelagic, secondarily aquatic tetrapods with more active swimming. Basilosaurids are therefore unique in the sense that
known to date. It also potentially represents the heaviest animal ever described.""Here we describe a basilosaurid whale that substantially pushes the upper limit of skeletal mass in mammals, as well as in aquatic vertebrates in general. This early whale combines a gigantic size and, to our knowledge, the strongest degree of BMI
So habit is inferred from bone density to conclude a niche unlike
anything known in extant whales. Could be.
On 8/4/23 09:26, John Harshman wrote:
On 8/2/23 9:34 PM, John Harshman wrote:
Can anyone describe the anatomy of Perucetus colossus, just published
in Nature, a middle Eocene whale claimed to be bigger than a blue
whale? An artist's conception shows it with a forelimb apparently with
free digits, being used to support the body above the sea floor.
Still can't see the article, but the public bits do include hints that
the only actual material includes only vertebrae and ribs, and the rest
of the skeleton is reconstructed based on presumed relatives. The tail
is even based on extant manatees. So, a bit of press release hype.
I get the idea that this guy might have been so old that
it might not have echolated a target like the modern grey
whale before diving.
Maybe it could just hold its breath for a longer period of
time?
what would be cool is if you could find something on the
formation of sonar among the cetaceans in general. Please
post if you could find something.
On Monday, August 7, 2023 at 1:15:01 PM UTC-4, John Harshman wrote:
On 8/7/23 9:53 AM, Peter Nyikos wrote:
On Friday, August 4, 2023 at 3:49:17 PM UTC-4, erik simpson wrote:
On Friday, August 4, 2023 at 9:27:02 AM UTC-7, John Harshman wrote: >>>>> On 8/2/23 9:34 PM, John Harshman started his first on-topic thread to s.b.p. that I recallever seeing.
Can anyone describe the anatomy of Perucetus colossus, just published in >>>>>> Nature, a middle Eocene whale claimed to be bigger than a blue whale? An >>>>>> artist's conception shows it with a forelimb apparently with free
digits, being used to support the body above the sea floor.
The artist's conception in the article does not show the digits to be free: the
body outline includes them.
We must be looking at different artist's conceptions. The one I'm
looking at is not in the Nature article.
Mine is.
FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.comThis one:
https://www.cnn.com/2023/08/02/world/ancient-colossal-whale-perucetus-colossus-scn/index.html
Still can't see the article, but the public bits do include hints that >>>>> the only actual material includes only vertebrae and ribs, and the rest >>>>> of the skeleton is reconstructed based on presumed relatives. The tail >>>>> is even based on extant manatees.
There is a tiny notch in the middle in Fig. 2. of the linked article below.
Note that the tail is entirely conjectural.
I was able to tell that just by looking at Figure 2, which shows what you write next:
The actual material consists
of some thoracic vertebrae, a few ribs, and a piece of the pelvis.
Strangely enough, a web search for "manatee tail" gave less than 5% photographs
showing a complete tail. Yet it is the quickest and easiest way to tell a manatee from a dugong.
So, a bit of press release hype.
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
sources really went to town.
First, I got a column of tiny reproductions of the pages that I was unable to magnify.
However, clicking a seemingly dead view-page button, I got a great webpage showing the article
and a note that I have access through the University of South Carolina library system.
The fossil is of some ribs and backbone, and they're extremely big and heavy. No evidence for what the skull or limbs were like, so body mass estimates are just that: estimates. It may likely be as big as a blue whate, or at least comparable. News
by additional deposition of bone on their external surface5 (that is, pachyostosis sensu stricto). BMI is documented in cetaceans’ amphibious close relatives11, as well as early members of the clade, the basilosaurids in particular.
The artist's conception on Fig. 2 makes it out to be substantially smaller, in the usual sense,
than the blue whale on the same illustration. However, where weight is concerned,
the abstract says,
"We use the skeletal fraction to estimate the body mass of P. colossus, which proves to be a contender for the title of heaviest animal on record."
In fact, the article seems to emphasize a condition that a certain insufferable self-advertiser
in s.b.p. and t.o. has advanced for a "waterside hypothesis" for proximal ancestors of *Homo*: pachyostosis.
"The adaptations of shallow-diving, slow-swimming species often comprise bone mass increase (BMI). This is produced by the infilling of the inner cavities of skeletal elements with compact bone (that is, osteosclerosis) and, in the more extreme cases,
The amphibious close relatives include *Ambulocetus*, the critter Stephen Jay Gould calledthat they acquired large sizes (up to around 20 m in body length3) and BMI. The degree of their BMI nevertheless did not match, up until now, that of some sirenians, for example, of which the whole rib cage is both strongly osteosclerotic and
"the smoking gun" of transition from terrestrial forms to archaeocetes ["early members of the clade"]
"Extant cetaceans have conversely acquired an entirely different bone microanatomy, with an osteoporotic-like structure typical of pelagic, secondarily aquatic tetrapods with more active swimming. Basilosaurids are therefore unique in the sense
known to date. It also potentially represents the heaviest animal ever described."
"Here we describe a basilosaurid whale that substantially pushes the upper limit of skeletal mass in mammals, as well as in aquatic vertebrates in general. This early whale combines a gigantic size and, to our knowledge, the strongest degree of BMI
Besides sirenians, the sea otter has been credited with being pachyostotic. I'm not sure about pinnepeds.
So habit is inferred from bone density to conclude a niche unlike
anything known in extant whales. Could be.
Confinement to shallow waters seems to be that niche. Do you
read the CNN article otherwise?
Confinement to shallow waters seems to be that niche. Do you
read the CNN article otherwise?
Sure. Why?
On 8/8/23 21:46, John Harshman wrote:
Confinement to shallow waters seems to be that niche. Do you
read the CNN article otherwise?
Sure. Why?
No damn way a monster that big is confined to shallow waters.
On Friday, August 11, 2023 at 9:55:00 PM UTC-4, Popping Mad wrote:small mollusks and crustaceans in sandy bottoms like the contemporary gray whale does. And thirdly, maybe Perucetus was a scavenger of vertebrate carcasses."
On 8/8/23 21:46, John Harshman wrote:
Confinement to shallow waters seems to be that niche. Do you
read the CNN article otherwise?
I'm not sure whether John's "Sure" refers to "otherwise." Here's what the CNN article says about that:Sure. Why?
"The authors didn’t have the animal’s skull or teeth, but its known characteristics indicate Perucetus likely fed near the bottom of the sea and wasn’t an active predator, Bianucci said.
...
The study authors have three hypotheses about Perucetus’ diet, Bianucci said: The whale might have been a plant eater like a sea cow, but this herbivorous diet would be the only case among cetaceans. Secondly, the ancient creature could have fed on
Why not look at the paper in Nature? CNN is hardly the place to be arguing about a very partial fossil.No damn way a monster that big is confined to shallow waters.I meant relatively shallow: I doubt that Perucetus strayed off the continental shelf,
which was wider than it is now, thanks to the lack of permanent icecaps. Peter Nyikos
Professor, Dept. of Mathematics -- standard disclaimer--
University of So. Carolina at Columbia
http://people.math.sc.edu/nyikos
On Monday, August 14, 2023 at 10:50:38 AM UTC-7, Peter Nyikos wrote:small mollusks and crustaceans in sandy bottoms like the contemporary gray whale does. And thirdly, maybe Perucetus was a scavenger of vertebrate carcasses."
On Friday, August 11, 2023 at 9:55:00 PM UTC-4, Popping Mad wrote:
On 8/8/23 21:46, John Harshman wrote:
Confinement to shallow waters seems to be that niche. Do you
read the CNN article otherwise?
I'm not sure whether John's "Sure" refers to "otherwise." Here's what the CNN article says about that:Sure. Why?
"The authors didn’t have the animal’s skull or teeth, but its known characteristics indicate Perucetus likely fed near the bottom of the sea and wasn’t an active predator, Bianucci said.
...
The study authors have three hypotheses about Perucetus’ diet, Bianucci said: The whale might have been a plant eater like a sea cow, but this herbivorous diet would be the only case among cetaceans. Secondly, the ancient creature could have fed on
No damn way a monster that big is confined to shallow waters.
I meant relatively shallow: I doubt that Perucetus strayed off the continental shelf,
which was wider than it is now, thanks to the lack of permanent icecaps.
Why not look at the paper in Nature?
CNN is hardly the place to be arguing about a very partial fossil.
On Friday, August 4, 2023 at 3:49:17 PM UTC-4, erik simpson wrote:FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.com
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
sources really went to town.The fossil is of some ribs and backbone, and they're extremely big and heavy. No evidence for what the skull or limbs were like, so body mass estimates are just that: estimates. It may likely be as big as a blue whate, or at least comparable. News
The artist's conception on Fig. 2 makes it out to be substantially smaller, in the usual sense,by additional deposition of bone on their external surface5 (that is, pachyostosis sensu stricto). BMI is documented in cetaceans’ amphibious close relatives11, as well as early members of the clade, the basilosaurids in particular. Extant cetaceans
than the blue whale on the same illustration. However, where weight is concerned,
the abstract says,
"We use the skeletal fraction to estimate the body mass of P. colossus, which proves to be a contender for the title of heaviest animal on record."
In fact, the article seems to emphasize a condition that a certain insufferable self-advertiser
in s.b.p. and t.o. has advanced for a "waterside hypothesis" for proximal ancestors of *Homo*: pachyostosis.
"The adaptations of shallow-diving, slow-swimming species often comprise bone mass increase (BMI). This is produced by the infilling of the inner cavities of skeletal elements with compact bone (that is, osteosclerosis) and, in the more extreme cases,
"Here we describe a basilosaurid whale that substantially pushes the upper limit of skeletal mass in mammals, as well as in aquatic vertebrates in general. This early whale combines a gigantic size and, to our knowledge, the strongest degree of BMIknown to date. It also potentially represents the heaviest animal ever described."
On 8/22/23 9:54 AM, Peter Nyikos wrote:FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.com
The new material here is about the smallest basilosaurid known, in tremendous
contrast from the topic up to now.
First, some context about the big one to bring out the contrast:
On Monday, August 7, 2023 at 12:53:56 PM UTC-4, Peter Nyikos wrote:
On Friday, August 4, 2023 at 3:49:17 PM UTC-4, erik simpson wrote:
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
Tutcetus allows us to further test hypotheses regarding basilosaurids’ early success in the aquatic ecosystem, which lasted into the latest Eocene, and their ability to outcompete amphibious stem whales and opportunistically adapt to new niches afterStill paywalled, no? The Nature article on the new one is not-- it's Open Access.
That's to be expected -- smallest, in such an obscure subject as basilosaurids,
is not apt to excite the general public. Here it is:
https://www.nature.com/articles/s42003-023-04986-w
Title: "A diminutive new basilosaurid whale reveals the trajectory of the cetacean life histories during the Eocene"
From the abstract:
"Here we report a new basilosaurid genus and species, Tutcetus rayanensis, from the middle Eocene of Fayum, Egypt. This new whale is not only the smallest known basilosaurid, but it is also one of the oldest records of this family from Africa.
The Nature article says:
"The new whale is the smallest basilosaurid known to date and is estimated to have been around 2.5 m in length and about 187 kg in body mass."
Fig. 1 has two remarkably clear pictures, which can be enlarged to show exquisite detail. Caption:
"Photograph (a) and corresponding explanatory line drawing (b) of the block containing the holotype specimen of T. rayanensis (MUVP 501)."
Fig. 2 shows even more detail of the molars [and premolars in (c)]: "Close-up of the posterior lower teeth in the left (b) and right (c) dentaries of Tutcetus rayanensis (MUVP 501, holotype).
Unlike in humans, the premolars are far bigger than the molars.
Scrolling way down, you see:
"Fig. 3: Phylogenetic position of Tutcetus rayanensis (MUVP 501, holotype)."
It shows 40 genera, divided into two largely terrestrial ones (Pakicetus and Ambulocetus),
five in the transitional Remingtonocetidae, including the first non-Indian, African genus;
16 in the Protocetidae including the well-known Rodhocetus, one genus from South America, and four from North America,
14 from Basilosauridae, which is truly world-wide, with the well-known Zyghoriza found in Europe,
North America, and Australasia. Here is where Tutcetus rayanensis is well nested.
Also 8 from Neoceti.
Patriotic note: one of the protocetids is Carolinacetus, found in Berkeley County, South Carolina.
The silhouette for it in Fig. 3 shows flippers [1] as advanced as in basilosaurids, except for the
hind ones being about twice as large, proportionately. More about it here:
https://en.wikipedia.org/wiki/Carolinacetus
[1] purely conjectural: the list of known bones in the Wiki article does not include any from any of the extremities.
Fig. 3 goes out of its way to obscure the (obvious to me) fact that all the above groups except
the last (and possibly the two-member first) are paraphyletic.
Not sure how you think it's trying to obscure that. It's obvious from
the figure. But only Basilosauridae and Protocetidae are shown as paraphyletic. That too is obvious from the figure.
And it's mentioned in the article, for example "Within the Pelagiceti
clade, the BTD analysis recovered Basilosauridae as paraphyletic, with Eocetus as the sister taxon of all other sampled members of Pelagiceti.
The lineage that gave rise to Eocetus is estimated to have split off
from all other members of Pelagiceti around 45 Ma, or around the start
of the middle Eocene (i.e., during the middle Lutetian substage). All
other basilosaurids (aside from Eocetus) and neocetes are included in a moderately-supported (PP = 0.67) clade that arises from the next-most crownward divergence from the cetacean stem lineage. "
On Tuesday, August 22, 2023 at 1:58:29 PM UTC-4, John Harshman wrote:FphQZ7HL6VlnC43Icnq8oDHLFKlxAl3o57ToObsIqf7HdMI9GUvv8oplw%3D&tracking_referrer=www.usatoday.com
On 8/22/23 9:54 AM, Peter Nyikos wrote:
The new material here is about the smallest basilosaurid known, in tremendous
contrast from the topic up to now.
First, some context about the big one to bring out the contrast:
On Monday, August 7, 2023 at 12:53:56 PM UTC-4, Peter Nyikos wrote:
On Friday, August 4, 2023 at 3:49:17 PM UTC-4, erik simpson wrote:
It isn't hard to get popular press articles, and it's also easy to the Nature connection:
https://www.nature.com/articles/s41586-023-06381-1.epdf?sharing_token=Km5bbE-eJJvo8mP-KmOLB9RgN0jAjWel9jnR3ZoTv0Pf_L6EYDYzR4YFKG3Aq8XzhCL-3NJFD3RlneHc9W_lt_6PQIXq0jLItmS3TbqH821xHn-LaTCXmsE4MGntzdBQRfFxe298jhlfUtBVbyE-x7uB7aH5VwT-4Y_K-lf-a-NB01Mov-
Tutcetus allows us to further test hypotheses regarding basilosaurids’ early success in the aquatic ecosystem, which lasted into the latest Eocene, and their ability to outcompete amphibious stem whales and opportunistically adapt to new niches after
Still paywalled, no? The Nature article on the new one is not-- it's Open Access.
That's to be expected -- smallest, in such an obscure subject as basilosaurids,
is not apt to excite the general public. Here it is:
https://www.nature.com/articles/s42003-023-04986-w
Title: "A diminutive new basilosaurid whale reveals the trajectory of the cetacean life histories during the Eocene"
From the abstract:
"Here we report a new basilosaurid genus and species, Tutcetus rayanensis, from the middle Eocene of Fayum, Egypt. This new whale is not only the smallest known basilosaurid, but it is also one of the oldest records of this family from Africa.
<snip for focus>
The Nature article says:
"The new whale is the smallest basilosaurid known to date and is estimated to have been around 2.5 m in length and about 187 kg in body mass."
Fig. 1 has two remarkably clear pictures, which can be enlarged to show exquisite detail. Caption:
"Photograph (a) and corresponding explanatory line drawing (b) of the block containing the holotype specimen of T. rayanensis (MUVP 501)."
Fig. 2 shows even more detail of the molars [and premolars in (c)]:
"Close-up of the posterior lower teeth in the left (b) and right (c) dentaries of Tutcetus rayanensis (MUVP 501, holotype).
Unlike in humans, the premolars are far bigger than the molars.
Scrolling way down, you see:
"Fig. 3: Phylogenetic position of Tutcetus rayanensis (MUVP 501, holotype)."
It shows 40 genera, divided into two largely terrestrial ones (Pakicetus and Ambulocetus),
five in the transitional Remingtonocetidae, including the first non-Indian, African genus;
16 in the Protocetidae including the well-known Rodhocetus, one genus from South America, and four from North America,
14 from Basilosauridae, which is truly world-wide, with the well-known Zyghoriza found in Europe,
North America, and Australasia. Here is where Tutcetus rayanensis is well nested.
Also 8 from Neoceti.
Patriotic note: one of the protocetids is Carolinacetus, found in Berkeley County, South Carolina.
The silhouette for it in Fig. 3 shows flippers [1] as advanced as in basilosaurids, except for the
hind ones being about twice as large, proportionately. More about it here: >>>
https://en.wikipedia.org/wiki/Carolinacetus
[1] purely conjectural: the list of known bones in the Wiki article does not include any from any of the extremities.
Fig. 3 goes out of its way to obscure the (obvious to me) fact that all the above groups except
the last (and possibly the two-member first) are paraphyletic.
Not sure how you think it's trying to obscure that. It's obvious from
the figure. But only Basilosauridae and Protocetidae are shown as
paraphyletic. That too is obvious from the figure.
You are right about that, but you may have jumped from the frying pan
into the fire. Fig. 3 makes Cetacea look polyphyletic!
Look at the node representing the LCA of Pakicetus and Ambulocetus.
The branches to the other cetaceans do NOT emanate from it,
but from the next node further down.
I can't help wondering what the tree would have looked like if *Indohyus* had been included.
It might have turned Cetacea into a clade, but then the following would be needing
a drastic overhaul.
"Indohyus is an extinct genus of digitigrade even-toed ungulates known from Eocene fossils in Asia. This small chevrotain-like animal found in the Himalayas is one of the earliest known non-cetacean ancestors of whales.[1]
https://en.wikipedia.org/wiki/Indohyus
[1] is here, courtesy of the Wayback machine: https://web.archive.org/web/20170504142727/https://www.ias.ac.in/article/fulltext/jbsc/034/05/0673-0686
Unsurprisingly, Thewissen is one of the co-authors.
And it's mentioned in the article, for example "Within the Pelagiceti
clade, the BTD analysis recovered Basilosauridae as paraphyletic, with
Eocetus as the sister taxon of all other sampled members of Pelagiceti.
The lineage that gave rise to Eocetus is estimated to have split off
from all other members of Pelagiceti around 45 Ma, or around the start
of the middle Eocene (i.e., during the middle Lutetian substage). All
other basilosaurids (aside from Eocetus) and neocetes are included in a
moderately-supported (PP = 0.67) clade that arises from the next-most
crownward divergence from the cetacean stem lineage. "
The article does not mention *Indohyus*. It roots the tree with the help
of a pig and a hippo.
On Monday, September 4, 2023 at 3:43:56 PM UTC-4, John Harshmantremendous
wrote:
On 9/4/23 6:36 AM, Peter Nyikos wrote:
On Tuesday, August 22, 2023 at 1:58:29 PM UTC-4, John Harshman
wrote:
On 8/22/23 9:54 AM, Peter Nyikos wrote:
The new material here is about the smallest basilosaurid
known, in
of the cetacean life histories during the Eocene"contrast from the topic up to now.
<snip for focus>
https://www.nature.com/articles/s42003-023-04986-w Title: "A
diminutive new basilosaurid whale reveals the trajectory
rayanensis, from the middle Eocene of Fayum, Egypt. This new whale is
From the abstract: "Here we report a new basilosaurid genus
and species, Tutcetus
estimated to have been around 2.5 m in length and about 187 kg in body mass."
<snip for focus>
The Nature article says:
"The new whale is the smallest basilosaurid known to date and
is
show exquisite detail. Caption:
Fig. 1 has two remarkably clear pictures, which can be
enlarged to
the block containing the holotype specimen of T. rayanensis (MUVP 501).""Photograph (a) and corresponding explanatory line drawing
(b) of
(c) dentaries of Tutcetus rayanensis (MUVP 501, holotype).
Fig. 2 shows even more detail of the molars [and premolars in
(c)]: "Close-up of the posterior lower teeth in the left (b)
and right
holotype)."
Unlike in humans, the premolars are far bigger than the
molars.
Scrolling way down, you see: "Fig. 3: Phylogenetic position
of Tutcetus rayanensis (MUVP 501,
(Pakicetus and Ambulocetus),
It shows 40 genera, divided into two largely terrestrial
ones
non-Indian, African genus;five in the transitional Remingtonocetidae, including the
first
genus from South America, and four from North America,16 in the Protocetidae including the well-known Rodhocetus,
one
well-known Zyghoriza found in Europe,14 from Basilosauridae, which is truly world-wide, with the
is well nested.North America, and Australasia. Here is where Tutcetus
rayanensis
Berkeley County, South Carolina.Also 8 from Neoceti.
Patriotic note: one of the protocetids is Carolinacetus,
found in
in basilosaurids, except for theThe silhouette for it in Fig. 3 shows flippers [1] as
advanced as
it here:hind ones being about twice as large, proportionately. More
about
article does not include any from any of the extremities.
https://en.wikipedia.org/wiki/Carolinacetus
[1] purely conjectural: the list of known bones in the Wiki
that all the above groups except
Fig. 3 goes out of its way to obscure the (obvious to me)
fact
*Indohyus* had been included.the last (and possibly the two-member first) are
paraphyletic.
Not sure how you think it's trying to obscure that. It's
obvious from the figure. But only Basilosauridae and
Protocetidae are shown as paraphyletic. That too is obvious
from the figure.
You are right about that, but you may have jumped from the frying
pan into the fire. Fig. 3 makes Cetacea look polyphyletic!
Look at the node representing the LCA of Pakicetus and
Ambulocetus. The branches to the other cetaceans do NOT emanate
from it, but from the next node further down.
How does that make Cetacea polyphyletic? I'm not getting your point
here.
See below.
I can't help wondering what the tree would have looked like if
would be needingIt might have turned Cetacea into a clade, but then the
following
known from Eocene fossils in Asia. This small chevrotain-like animala drastic overhaul.
"Indohyus is an extinct genus of digitigrade even-toed ungulates
https://en.wikipedia.org/wiki/Indohyus
I'm not sure what you're trying to say there either. First, of
courses, "ancestors" is misused here, as we can't tell whether
Indohyus is ancestral to anything.
It is being hypothesized as such, but IIRC reference [1] does not do
that.
missing from someAnd "earliest known" is a problem, since the non-cetacean ancestors
of whales go back to the origin of life. What I think it meant to
say is that Indohyus is the known non-cetacean most closely related
to Cetacea, i.e. the closest outgroup. Thus it would fall on a
branch in between hippos and the base of Cetacea.
Still, Cetacea is a clade in Fig. 3, with or without Indohyus.
Sorry, you can't make a valid taxon out of something where the data
is
key nodes at the bottom. The LCA of the two strictly data-definedLCA's (that of Pakicetus
and Ambulocetus, and that of all the other genera) could be asnon-cetacean
as *Indohyus* for all you know. But that LCA of LCA's is what isneeded to make a clade out of Cetacea.
If you want a long-acknowledged example of this kind of problem,at what is said
look
in Romer's _Vertebrate Paleontology_ about the phylogeny of thegarfish and the bowfin
(in Semionotoidea and Amoidea, respectively).76, and
These are "holostean" fish, but the evolutionary tree in fig. 60
shows how Holostei is polyphyletic. In the 1945 edition, it is on p.
its caption is: "Development of the groups of bony fishes andand explicitly mentioned
amphibians." The polyphyly is explained on page 94 in the section "Subholosteans"
earlier, p. 87, in the section "Ray-finned fishes," where we read:The tree shows no such thing. It's ambiguous because there's an apparent polytomy at the base of Holostei. Could be polyphyletic, could be
"the holostean level of organization was surely attained by morepolyphyletic."
thanone group of primitive forms, and the teleosts may be similarly
Don't know why they used those two taxa, but the hippo is obvious, and I supposed they wanted another artiodactyl. Trees with multiple outgroups[1] is here, courtesy of the Wayback machine:
https://web.archive.org/web/20170504142727/https://www.ias.ac.in/article/fulltext/jbsc/034/05/0673-0686
Unsurprisingly, Thewissen is one of the co-authors.
And it's mentioned in the article, for example "Within the
Pelagiceti clade, the BTD analysis recovered Basilosauridae as
paraphyletic, with Eocetus as the sister taxon of all other
sampled members of Pelagiceti. The lineage that gave rise to
Eocetus is estimated to have split off from all other members
of Pelagiceti around 45 Ma, or around the start of the middle
Eocene (i.e., during the middle Lutetian substage). All other
basilosaurids (aside from Eocetus) and neocetes are included in
a moderately-supported (PP = 0.67) clade that arises from the
next-most crownward divergence from the cetacean stem lineage.
"
The article does not mention *Indohyus*. It roots the tree with
the help of a pig and a hippo.
True enough.
By the way, why do you think they used two taxa for the rooting? I
don't recall coming across any trees that used more than one before.
On 9/4/23 6:36 AM, Peter Nyikos wrote:
On Tuesday, August 22, 2023 at 1:58:29 PM UTC-4, John Harshman wrote:
On 8/22/23 9:54 AM, Peter Nyikos wrote:
The new material here is about the smallest basilosaurid known, in tremendous
contrast from the topic up to now.
Tutcetus allows us to further test hypotheses regarding basilosaurids’ early success in the aquatic ecosystem, which lasted into the latest Eocene, and their ability to outcompete amphibious stem whales and opportunistically adapt to new niches afterhttps://www.nature.com/articles/s42003-023-04986-w
Title: "A diminutive new basilosaurid whale reveals the trajectory of the cetacean life histories during the Eocene"
From the abstract:
"Here we report a new basilosaurid genus and species, Tutcetus rayanensis, from the middle Eocene of Fayum, Egypt. This new whale is not only the smallest known basilosaurid, but it is also one of the oldest records of this family from Africa.
<snip for focus>
The Nature article says:
"The new whale is the smallest basilosaurid known to date and is estimated to have been around 2.5 m in length and about 187 kg in body mass."
Fig. 1 has two remarkably clear pictures, which can be enlarged to show exquisite detail. Caption:
"Photograph (a) and corresponding explanatory line drawing (b) of the block containing the holotype specimen of T. rayanensis (MUVP 501)."
Fig. 2 shows even more detail of the molars [and premolars in (c)]:
"Close-up of the posterior lower teeth in the left (b) and right (c) dentaries of Tutcetus rayanensis (MUVP 501, holotype).
Unlike in humans, the premolars are far bigger than the molars.
Scrolling way down, you see:
"Fig. 3: Phylogenetic position of Tutcetus rayanensis (MUVP 501, holotype)."
It shows 40 genera, divided into two largely terrestrial ones (Pakicetus and Ambulocetus),
five in the transitional Remingtonocetidae, including the first non-Indian, African genus;
16 in the Protocetidae including the well-known Rodhocetus, one genus from South America, and four from North America,
14 from Basilosauridae, which is truly world-wide, with the well-known Zyghoriza found in Europe,
North America, and Australasia. Here is where Tutcetus rayanensis is well nested.
Also 8 from Neoceti.
Patriotic note: one of the protocetids is Carolinacetus, found in Berkeley County, South Carolina.
The silhouette for it in Fig. 3 shows flippers [1] as advanced as in basilosaurids, except for the
hind ones being about twice as large, proportionately. More about it here:
https://en.wikipedia.org/wiki/Carolinacetus
[1] purely conjectural: the list of known bones in the Wiki article does not include any from any of the extremities.
Fig. 3 goes out of its way to obscure the (obvious to me) fact that all the above groups except
the last (and possibly the two-member first) are paraphyletic.
Not sure how you think it's trying to obscure that. It's obvious from
the figure. But only Basilosauridae and Protocetidae are shown as
paraphyletic. That too is obvious from the figure.
You are right about that, but you may have jumped from the frying pan
into the fire. Fig. 3 makes Cetacea look polyphyletic!
Look at the node representing the LCA of Pakicetus and Ambulocetus.
The branches to the other cetaceans do NOT emanate from it,
but from the next node further down.
How does that make Cetacea polyphyletic? I'm not getting your point here.
I can't help wondering what the tree would have looked like if *Indohyus* had been included.
It might have turned Cetacea into a clade, but then the following would be needing
a drastic overhaul.
"Indohyus is an extinct genus of digitigrade even-toed ungulates known from Eocene fossils in Asia. This small chevrotain-like animal found in the Himalayas is one of the earliest known non-cetacean ancestors of whales.[1]
https://en.wikipedia.org/wiki/Indohyus
I'm not sure what you're trying to say there either. First, of courses, "ancestors" is misused here, as we can't tell whether Indohyus is
ancestral to anything.
And "earliest known" is a problem, since the
non-cetacean ancestors of whales go back to the origin of life. What I
think it meant to say is that Indohyus is the known non-cetacean most closely related to Cetacea, i.e. the closest outgroup. Thus it would
fall on a branch in between hippos and the base of Cetacea.
Still, Cetacea is a clade in Fig. 3, with or without Indohyus.
[1] is here, courtesy of the Wayback machine: https://web.archive.org/web/20170504142727/https://www.ias.ac.in/article/fulltext/jbsc/034/05/0673-0686
Unsurprisingly, Thewissen is one of the co-authors.
And it's mentioned in the article, for example "Within the Pelagiceti
clade, the BTD analysis recovered Basilosauridae as paraphyletic, with
Eocetus as the sister taxon of all other sampled members of Pelagiceti. >> The lineage that gave rise to Eocetus is estimated to have split off
from all other members of Pelagiceti around 45 Ma, or around the start >> of the middle Eocene (i.e., during the middle Lutetian substage). All
other basilosaurids (aside from Eocetus) and neocetes are included in a >> moderately-supported (PP = 0.67) clade that arises from the next-most >> crownward divergence from the cetacean stem lineage. "
The article does not mention *Indohyus*. It roots the tree with the help of a pig and a hippo.
True enough.
On 9/4/23 6:25 PM, Peter Nyikos wrote:<snip for focus>
On Monday, September 4, 2023 at 3:43:56 PM UTC-4, John Harshmantremendous
wrote:
On 9/4/23 6:36 AM, Peter Nyikos wrote:
On Tuesday, August 22, 2023 at 1:58:29 PM UTC-4, John Harshman
wrote:
On 8/22/23 9:54 AM, Peter Nyikos wrote:
The new material here is about the smallest basilosaurid
known, in
contrast from the topic up to now.
<snip for focus>
of the cetacean life histories during the Eocene"https://www.nature.com/articles/s42003-023-04986-w Title: "A
diminutive new basilosaurid whale reveals the trajectory
holotype)."Scrolling way down, you see: "Fig. 3: Phylogenetic position
of Tutcetus rayanensis (MUVP 501,
It shows 40 genera, divided into two largely terrestrial
ones (Pakicetus and Ambulocetus),
five in the transitional Remingtonocetidae, including the
first non-Indian, African genus;
16 in the Protocetidae including the well-known Rodhocetus,
one genus from South America, and four from North America,
14 from Basilosauridae, which is truly world-wide, with the
well-known Zyghoriza found in Europe, North America, and Australasia. >>>>> Here is where Tutcetus rayanensis is well nested.
Also 8 from Neoceti.
only Basilosauridae and Protocetidae are shown as paraphyletic.
That too is obvious from the figure.
You are right about that, but you may have jumped from the frying
pan into the fire. Fig. 3 makes Cetacea look polyphyletic!
Look at the node representing the LCA of Pakicetus and
Ambulocetus. The branches to the other cetaceans do NOT emanate
from it, but from the next node further down.
How does that make Cetacea polyphyletic? I'm not getting your point here.
See below.
I can't help wondering what the tree would have looked like if *Indohyus* had been included.
It might have turned Cetacea into a clade, but then the following would be needing
a drastic overhaul.
"Indohyus is an extinct genus of digitigrade even-toed ungulates known from Eocene fossils in Asia. This small chevrotain-like animal found in the Himalayas is one of the earliest known non-cetacean ancestors of whales.[1]
https://en.wikipedia.org/wiki/Indohyus
I'm not sure what you're trying to say there either. First, of
courses, "ancestors" is misused here, as we can't tell whether
Indohyus is ancestral to anything.
It is being hypothesized as such, but IIRC reference [1] does not do
that.
And "earliest known" is a problem, since the non-cetacean ancestors
of whales go back to the origin of life. What I think it meant to
say is that Indohyus is the known non-cetacean most closely related
to Cetacea, i.e. the closest outgroup. Thus it would fall on a
branch in between hippos and the base of Cetacea.
Still, Cetacea is a clade in Fig. 3, with or without Indohyus.
Sorry, you can't make a valid taxon out of something where the data is missing from some key nodes at the bottom. The LCA of the two strictly data-defined
LCA's (that of Pakicetus and Ambulocetus, and that of all the other genera)
I'm not understanding your point here. There's some assumption you're
making that I don't see. I can't tell what you mean by "strictly data-defined", or how that node differs from any other.
If you want a long-acknowledged example of this kind of problem,
look at what is said
in Romer's _Vertebrate Paleontology_ about the phylogeny of the
garfish and the bowfin (in Semionotoidea and Amoidea, respectively).
These are "holostean" fish, but the evolutionary tree in fig. 60
shows how Holostei is polyphyletic. In the 1945 edition, it is on p. 76, and its caption is: "Development of the groups of bony fishes and amphibians." The polyphyly is explained on page 94 in the section "Subholosteans" and explicitly mentioned
earlier, p. 87, in the section "Ray-finned fishes," where we read:
The tree shows no such thing. It's ambiguous because there's an apparent polytomy at the base of Holostei.
paraphyletic. At any rate, it's nothing like what the cetacean tree
shows, which is clear monophyly.
Of course that depends on your definition of Cetacea, whether
node-based, branch-based, or character-based, and on what other taxa you
put on the tree, and just where they turn up. But based on the figure, there's no reason to doubt monophyly and there's nothing different
between the two nodes you mention.
On Monday, September 4, 2023 at 9:49:58 PM UTC-4, John Harshman wrote:
On 9/4/23 6:25 PM, Peter Nyikos wrote:<snip for focus>
On Monday, September 4, 2023 at 3:43:56 PM UTC-4, John Harshmantremendous
wrote:
On 9/4/23 6:36 AM, Peter Nyikos wrote:
On Tuesday, August 22, 2023 at 1:58:29 PM UTC-4, John Harshman
wrote:
On 8/22/23 9:54 AM, Peter Nyikos wrote:
The new material here is about the smallest basilosaurid
known, in
of the cetacean life histories during the Eocene"contrast from the topic up to now.
<snip for focus>
https://www.nature.com/articles/s42003-023-04986-w Title: "A
diminutive new basilosaurid whale reveals the trajectory
holotype)."Scrolling way down, you see: "Fig. 3: Phylogenetic position
of Tutcetus rayanensis (MUVP 501,
It shows 40 genera, divided into two largely terrestrial
ones (Pakicetus and Ambulocetus),
five in the transitional Remingtonocetidae, including the
first non-Indian, African genus;
16 in the Protocetidae including the well-known Rodhocetus,
one genus from South America, and four from North America,
14 from Basilosauridae, which is truly world-wide, with the
well-known Zyghoriza found in Europe, North America, and Australasia. >>>>>>> Here is where Tutcetus rayanensis is well nested.
Also 8 from Neoceti.
<snip for focus>
See below.only Basilosauridae and Protocetidae are shown as paraphyletic.
That too is obvious from the figure.
You are right about that, but you may have jumped from the frying
pan into the fire. Fig. 3 makes Cetacea look polyphyletic!
Look at the node representing the LCA of Pakicetus and
Ambulocetus. The branches to the other cetaceans do NOT emanate
from it, but from the next node further down.
How does that make Cetacea polyphyletic? I'm not getting your point here. >>>
I can't help wondering what the tree would have looked like if *Indohyus* had been included.
It might have turned Cetacea into a clade, but then the following would be needing
a drastic overhaul.
"Indohyus is an extinct genus of digitigrade even-toed ungulates known from Eocene fossils in Asia. This small chevrotain-like animal found in the Himalayas is one of the earliest known non-cetacean ancestors of whales.[1]
https://en.wikipedia.org/wiki/Indohyus
I'm not sure what you're trying to say there either. First, of
courses, "ancestors" is misused here, as we can't tell whether
Indohyus is ancestral to anything.
It is being hypothesized as such, but IIRC reference [1] does not do
that.
And, of course, the dominant attitude in "modern" systematics is,
"Sister group hypotheses good, ancestor-descendant hypotheses bad!"
This makes about as much sense as "Four legs good, two legs bad!"
in George Orwell's _Animal_Farm_.
And "earliest known" is a problem, since the non-cetacean ancestors
of whales go back to the origin of life. What I think it meant to
say is that Indohyus is the known non-cetacean most closely related
to Cetacea, i.e. the closest outgroup. Thus it would fall on a
branch in between hippos and the base of Cetacea.
Still, Cetacea is a clade in Fig. 3, with or without Indohyus.
Sorry, you can't make a valid taxon out of something where the data is
missing from some key nodes at the bottom. The LCA of the two strictly data-defined
LCA's (that of Pakicetus and Ambulocetus, and that of all the other genera)
It's worse than I wrote above, through not defining what I meant by "strictly data-defined LCA".
What I had in mind is "each node has at least one genus directly emanating from it,
with no intermediate nodes [1]". I just wasn't careful enough in applying it.
So, "all the other genera" have an LCA of two strictly defined LCA's, [2] one of Remingtonocetidae
(which has the genus Dalanistes directly emanating from it), the other of Eocetidae, which
has the genus Maiacetus directly emanating from it.
[1] Of course, if the tree had species instead of genera at the branch tips, then "strictly" would apply
to directly emanating species.
[2] I call strictly defined LCA's "first-order LCA's", and a "second-order LCA"
is a non-first-order LCA of two first-order LCA's. Thus "all other genera" have a second-order LCA.
The LCA of Cetacea is not even a second-order LCA, but it is third-order because each LCA to which it directly connects is either first-order
[as in the case of {Pakicetus, Ambulocetus}] or second-order.
This third-order LCA could be as non-cetacean as *Indohyus* for all you know. But that is what is needed to make Cetacea a clade.
I'm not understanding your point here. There's some assumption you're
making that I don't see. I can't tell what you mean by "strictly
data-defined", or how that node differs from any other.
I hope the above explanation is clear enough for you to admit
to being able to follow it.
If the whole concept of "nth order LCA" is foreign to you,
then the reigning systematists are ignoring important distinctions.
The higher the order of an LCA, the less secure the information you have about
the characters of the <cough> "hypothetical" <cough> animal that it represents.
If you want a long-acknowledged example of this kind of problem,
look at what is said
in Romer's _Vertebrate Paleontology_ about the phylogeny of the
garfish and the bowfin (in Semionotoidea and Amoidea, respectively).
These are "holostean" fish, but the evolutionary tree in fig. 60
shows how Holostei is polyphyletic. In the 1945 edition, it is on p. 76, >>> and its caption is: "Development of the groups of bony fishes and
amphibians." The polyphyly is explained on page 94 in the section
"Subholosteans" and explicitly mentioned
earlier, p. 87, in the section "Ray-finned fishes," where we read:
The tree shows no such thing. It's ambiguous because there's an apparent
polytomy at the base of Holostei.
You are looking too far up. The polyphyletic nature of Holostei
is shown further down, where Semionotoidea and the paraphyletic
Subholostei emanate from two different places in Palaeonscoidea.
Subholostei in turn gives rise to Amoidea and all the other "holostean" superfamilies.
VCould be polyphyletic, could be
paraphyletic. At any rate, it's nothing like what the cetacean tree
shows, which is clear monophyly.
With a possibly non-cetacean LCA!! see above.
Of course that depends on your definition of Cetacea, whether
node-based, branch-based, or character-based, and on what other taxa you
put on the tree, and just where they turn up. But based on the figure,
there's no reason to doubt monophyly and there's nothing different
between the two nodes you mention.
Again, you systematists don't pay enough attention to distinctions,
just as paleontologists of the first half of the 20th century
showed sauropods snorkeling at the ends of their long necks
while ignoring increased pressure at the depth of their lungs,
making breathing impossible.
Too much stamp collecting and not enough mathematics/physics,
as the old saying about "all science" goes. Mathematicians
are used to making distinctions, y'all are wedded to distinctions
born of Hennig.
On 9/4/23 6:25 PM, Peter Nyikos wrote:
look at what is said in Romer's _Vertebrate Paleontology_
about the phylogeny of the garfish and the bowfin
(in Semionotoidea and Amoidea, respectively).
These are "holostean" fish, but the evolutionary tree in fig. 60
shows how Holostei is polyphyletic. In the 1945 edition, it is on p. 76, and
its caption is: "Development of the groups of bony fishes and
amphibians." The polyphyly is [...] explicitly mentioned
[on] p. 87, in the section "Ray-finned fishes," where we read:
"the holostean level of organization was surely attained by more
than one group of primitive forms, and the teleosts may be similarly
polyphyletic."
Yes, Romer was really into polyphyly.
He thought mammals were too.
He was wrong about both.
If I recall, holosteans are paraphyletic, not
polyphyletic. But I don't see the relevance here. Still not getting what you're trying to say.
[1] is here, courtesy of the Wayback machine:
https://web.archive.org/web/20170504142727/https://www.ias.ac.in/article/fulltext/jbsc/034/05/0673-0686
Unsurprisingly, Thewissen is one of the co-authors.
And it's mentioned in the article, for example "Within the
Pelagiceti clade, the BTD analysis recovered Basilosauridae as
paraphyletic, with Eocetus as the sister taxon of all other
sampled members of Pelagiceti. The lineage that gave rise to
Eocetus is estimated to have split off from all other members
of Pelagiceti around 45 Ma, or around the start of the middle
Eocene (i.e., during the middle Lutetian substage). All other
basilosaurids (aside from Eocetus) and neocetes are included in
a moderately-supported (PP = 0.67) clade that arises from the
next-most crownward divergence from the cetacean stem lineage.
"
The article does not mention *Indohyus*. It roots the tree with
the help of a pig and a hippo.
True enough.
By the way, why do you think they used two taxa for the rooting? I
don't recall coming across any trees that used more than one before.
Don't know why they used those two taxa, but the hippo is obvious, and I supposed they wanted another artiodactyl. Trees with multiple outgroups
are not at all rare, though. It's considered good form to break up long branches whenever possible.
Family and university needs have really cut into my free time,
disrupting my posting plans. This is the second and final reply to this post of 4 days ago.
On Monday, September 4, 2023 at 9:49:58 PM UTC-4, John Harshman wrote:
On 9/4/23 6:25 PM, Peter Nyikos wrote:
look at what is said in Romer's _Vertebrate Paleontology_
about the phylogeny of the garfish and the bowfin
(in Semionotoidea and Amoidea, respectively).
These are "holostean" fish, but the evolutionary tree in fig. 60
shows how Holostei is polyphyletic. In the 1945 edition, it is on p. 76, and
its caption is: "Development of the groups of bony fishes and
amphibians." The polyphyly is [...] explicitly mentioned
[on] p. 87, in the section "Ray-finned fishes," where we read:
<snip of later text, dealt with in my first reply>
"the holostean level of organization was surely attained by more
than one group of primitive forms, and the teleosts may be similarly
polyphyletic."
Yes, Romer was really into polyphyly.
He explained that in the very next sentence wrt fishes:
"However, this type of classification, even if not entirely natural,
is one which it is best to preserve until our knowledge of the
complex evolutionary history of the ray-finned fishes is much more
adequate than is the case at present."
He thought mammals were too.
Why are you so skimpy with the details? Do you believe that
no one besides the two of us is reading this?
You are making this claim because the tree in the chapter "Primitive Mammals"
shows monotremes in a lineage disconnected from all the mammals
known at the time, all subsumed under Theria. These included
all the Mesozoic mammals known from fossils back then:
"the aberrant multituberculates," the paraphyletic pantotheres,
the triconodonts and the symmetrodonts.
And guess what: Carroll, in his 1988 _Vertebrate Paleontology and Evolution_, has a tree on page 415, which shows monotremes in the same "way out" way
as Romer did. Even Morganucodon, now believed to be outside the
mammalian crown group [but WHY?] is closer to those Romer-designated Therians in the tree than the monotremes are.
He was wrong about both.
Then so was Carroll. But what makes you so all-fired certain that these experts were wrong? How certain are you, for instance, that
Theropods are closer to Sauropods than they are to Ornithischians?
If I recall, holosteans are paraphyletic, not
polyphyletic. But I don't see the relevance here. Still not getting what
you're trying to say.
See my first reply to this same post of yours for both sentences.
https://web.archive.org/web/20170504142727/https://www.ias.ac.in/article/fulltext/jbsc/034/05/0673-0686[1] is here, courtesy of the Wayback machine:
Unsurprisingly, Thewissen is one of the co-authors.
And it's mentioned in the article, for example "Within the
Pelagiceti clade, the BTD analysis recovered Basilosauridae as
paraphyletic, with Eocetus as the sister taxon of all other
sampled members of Pelagiceti. The lineage that gave rise to
Eocetus is estimated to have split off from all other members
of Pelagiceti around 45 Ma, or around the start of the middle
Eocene (i.e., during the middle Lutetian substage). All other
basilosaurids (aside from Eocetus) and neocetes are included in
a moderately-supported (PP = 0.67) clade that arises from the
next-most crownward divergence from the cetacean stem lineage.
"
The article does not mention *Indohyus*. It roots the tree with
the help of a pig and a hippo.
True enough.
By the way, why do you think they used two taxa for the rooting? I
don't recall coming across any trees that used more than one before.
Don't know why they used those two taxa, but the hippo is obvious, and I
supposed they wanted another artiodactyl. Trees with multiple outgroups
are not at all rare, though. It's considered good form to break up long
branches whenever possible.
Does this have anything to do with long branch attractors?
In this case, all it supports is the idea that hippos are the sister group
of cetaceans, and that entails not just one long branch, but the two we see in the tree.
| Sysop: | Keyop |
|---|---|
| Location: | Huddersfield, West Yorkshire, UK |
| Users: | 715 |
| Nodes: | 16 (3 / 13) |
| Uptime: | 28:31:42 |
| Calls: | 12,107 |
| Calls today: | 7 |
| Files: | 15,006 |
| Messages: | 6,518,231 |