While it is true that I often like to talk about mammary glands to add a little humor to these threads, this discussion has nothing to do with them. It is about the transformation CLAIMED by evolutionists of the egg laying reproductive system of the reptiles into the live birth reproductive system of mammals.
The reptile-mammal transition is particularly visible in the fossil record.
No it is not. It's not about earbones, it's about internal organs and there is not a single bit of evidence about the development of those internal organs so you have no evidence on the question which I have been asking for a few months and which Dan Day tried to refute in Post# 378 and I convincingly dismissed in Post# 425 which is that a species cannot transform its mode of reproduction in a single generation which is what would perforce be necessary in the case of the purported reptile/mammal transformation.
What you have to refute is the scientific details in my post# 425 and show from your marvelous evolutionist writers how this TRANSFORMATION OF THE REPRODUCTIVE SYSTEM occurred in a single generation, not talk to me about earbones.
Psst: UC Riverside study suggests placentas can evolve in 750,000 years or less
and which Dan Day tried to refute in Post# 378 and I convincingly dismissed in Post# 425
*snort*. Pretty cocky, aren't you? Check out my critique of your "dismissal" in post #509.
How many people how many times have to explain to you what evolutionists actually claim so you can get on topic? Can you read?
It is about--corrected version here--the transformation claimed by evolutionists of the egg-laying reproductive system of mammals (like the still-extant monotremes) to the live-birth strategies of the marsupials and placentals. Mammals were mammals before they had any kind of live birth.
First, mammal-like reptiles diverged from other reptile lineages. That was far back, not long after the appearance of basal reptiles. Some lineages of mammal-like reptiles experimented with warm-bloodedness and with walking up completely on the legs (as opposed to dragging the belly and merely pushing with the legs).
Reptile ears aren't very good with the head out of contact with the ground. Thus, some of the high-walkers coopted their rearward lower jaw bones to resonate with the original reptilian earbone and enhance their hearing. This wasn't as hard as it may sound, since reptiles have losely-jointed, expandable jaws for swallowing large objects whole.
Eventually, this second useage of the rearward jawbones overwhelmed the original one. A "double-joint" allowed the use of a single bone for chewing and biting and completely freed the rearmost lower jaw bones for hearing.
This transition, well documented in the fossil record, is where taxonomists draw a line and say, "From here forward, we call them mammals." Admittedly, they pick this point as much because you can't see in the fossil record if a creature had mammary glands, or bore scales versus fur. (Fur isn't exactly diagnostic anyway as, for one thing, there's evidence for fur in pterosaurs, diapsid reptiles more related to dinosaurs than to mammals. But nothing else in nature has those ear bones.)
Later yet, some time after the monotremes had diverged from the basal mammal stock, mammals experimented with live-birth schemes. Marsupials are one result. Placentals are the latest and most successful.
Now do you understand what Dan Day's 378 is about?