Why humans no longer have tails ..

[BeyondET]

It's a rare birth defect. It's not vestigial. Source.

No he is right,

A clip from the link you provided below.

Historically, the pseudotail has been the one associated with birth defects, and as such, it is not considered vestigial.

As it turns out, both rare appendages probably represent an incomplete fusion of the spinal column, or what's known as a spinal dysraphism.

 

[BeyondET]

I can see I'm talkin' with people who apparently can't read the quote in the OP!(?)

People have read it, so did I and it doesn't say humans once had a tail and lost it as the title says that's what people are pointing out.

They have no idea where humans came from certainly not mice which share 80% of human DNA.

 

[SelfSim]

Then there's ghost DNA, unknown hominin from long ago, human origin is very complex.

https://www.npr.org/2020/02/12/805237120/ghost-dna-in-west-africans-complicates-story-of-human-origins

Not relevant to the OP timframe of 25mya:

The scientists think the interbreeding happened about 50,000 years ago, ..

 

[BeyondET]

Not relevant to the OP timframe of 25mya:

Yes I agree the title isn't relevant with the links posted. Because there is unknown human DNA which means more to the story of human origin.

The links have no idea if humans came from tailed beings. They don't even know what precursor so it's all speculation. Especially to think it was 50,000 years ago.

Certainly humans don't share 50% of their DNA with a banana because of inbreeding.

 

[BeyondET]

Human share 80% of dna with a mouse, there is no way scientists can track human orgin. What they see in genes of species just might be another mouse or banana.

 

[SelfSim]

Yes I agree the title isn't relevant with the links posted. Because there is unknown human DNA which means more to the story of human origin.

The links have no idea if humans came from tailed beings. They don't even know what precursor so it's all speculation. Especially to think it was 50,000 years ago.

Certainly humans don't share 50% of their DNA with a banana because of inbreeding.

Human share 80% of dna with a mouse, there is no way scientists can track human orgin. What they see in genes of species just might be another mouse or banana.

Coming back to the tail issue in humans, from the Konkel/Casanova paper:

The lack of a tail is one thing that separates apes — including humans — from other primates.
...
Tails are a common feature in the animal kingdom, and all mammals have a tail at some point during embryonic development. In humans, the tail disappears at the end of the embryonic phase — approximately eight weeks in utero — although internal parts remain in the form of the tailbone.

 

[BeyondET]

Coming back to the tail issue in humans, from the Konkel/Casanova paper:

And humans have gills during embryonic development does that mean fish are human ancestors, indeed everything returns to the dirt but humans don't know which grain went where.

 

[Ophiolite]

What creationists call "Junk DNA" is known by scientists as "non-coding DNA." Some of it, like our broken vitamin C gene, is junk. But a lot of it has other functions.

Last time I looked, they were still calling it "junk DNA."

The term junk DNA was not coined by creationists but by geneticists. The wikipedia article covers this and provides appropriate links on the matter.

A similar error occurs when the term evolutionist is attributed to creationists as a supposedly perjorative term. If being considered an evolutionist was good enough for Ernst Mayr, it's a badge I'll wear with pride.

 

[sfs]

What creationists call "Junk DNA" is known by scientists as "non-coding DNA." Some of it, like our broken vitamin C gene, is junk. But a lot of it has other functions.

No, junk DNA is noncoding DNA (almost always, anyway), but there's lots of functional noncoding DNA as well. Junk DNA only refers to the parts that don't have function.

 

[sfs]

On a more serious note the article states: "Interestingly, these elements reside in introns, sections of DNA flanking exons that were traditionally deemed non-functional "dark matter."
Does this count as what has been referred to as junk DNA?

Yes. The intronic DNA in question, prior to the Alu insertion, was (as far as I known) indeed nonfunctional. The insertion was a gain-of-function mutation that created a new splice site for that gene. So now it's functional but it wasn't before.

A term that those who introduced it are likely now regretting.

I think they're all dead now, so if they're regretting it, they're doing so out of sight. But why should they regret it? Most human DNA is nonfunctional, and 'junk' is a fine word to describe DNA that doesn't do anything useful.

 

[Lost4words]

I find that because of my tail, i get a better signal on my mobile phone when out and about.

 

[Ophiolite]

I think they're all dead now, so if they're regretting it, they're doing so out of sight. But why should they regret it? Most human DNA is nonfunctional, and 'junk' is a fine word to describe DNA that doesn't do anything useful.

The impression I have is that a proportion, all be it small, of what was said to be junk has subsequently proved to be functional. Thus its description as junk, in those cases, was premature.

 

[sfs]

The impression I have is that a proportion, all be it small, of what was said to be junk has subsequently proved to be functional. Thus its description as junk, in those cases, was premature.

Sure. In a similar way, a proportion of what were thought to be genes have subsequently turned out not to be. Exactly what sequence belongs in what category is always subject to revision with more information, but the categories themselves are still useful. (That's true even though both 'gene' and 'junk DNA' have fuzzy boundaries as categories.)

 

[SelfSim]

So now it's functional but it wasn't before.

Re: (the underlined) .. which was a 'post-diction' based on the study's lab-based testing on (mammalian) mice.
Humans also have a corresponding gene that functions in the same way, although it does seem there may be other influences when it comes to embryonic tail development and cessation thereof in humans(?)