Secondary ectothermy has been suggested in living crocodylians by Seymour et al. (2004). Their rationale is based on:
Presence of a 4 chambered heart (otherwise only found in endotherms)
Post-cardiac shunting via the foramen of Panizza and "cog-tooth" valve, which develop secondarily in crocodylians
Lung structure and ventilation during locomotion
By the picture and the official distribution it looks to be as you said a Lacerta viridis.
Some references and distribution here:
In Western Europe we have a brother specie ...
It's a self-defense mechanism, the tail falls off during threatening situations, to which the reptile responds by excessively contracting the tail muscles. This process is known as "Autotomy", or "Self-Amputation". Other animals have got "stronger tails" simply because such self-defense mechanism hasn't been developed.
The picture looks like it's from the Cerastes genus. It looks similar to a head shot of Cerastes Cerastes (Saharan horned viper) shown on Wikipedia:
In fact, the incident you describe is also reported in Wikipedia's Cerastes Cerastes article since it could be the first sighting in Pakistan. However, I sincerely (and respectfully) doubt that this snake was ...
There is no evolutionary "ratchet" that prevents a life form from evolving "backwards". However, it is statistically unlikely because it would pretty much require all of the environmental factors that changed during the transition from "cold blooded" to "warm-blooded" to change back in the reverse order, because all of those factors contributed to the ...
I finally got frustrated enough to dig up A Revision of the Liasis childreni species-group (Serpentes: Boidae) L.A. Smith, 1985 - the original paper that split up this species complex, and when even Smith made primary determinations off of pattern and color alone, I took matters into my own hands and dug into the his raw data.
I have compiled the mean ...
The triangular pattern and the lightly colored underside resemble typical patterns of Bothrops (lancehead viper). Without the head it is quite difficult to tell which species this is. Given the location, the most common lancehead viper would be Bothrops jajaraca, simply called Jararaca by the locals.
Images can be found here
Yes, this is almost certainly Bufo bufo.
It has the stocky figure and the warty skin, ruling out the true frogs.
It lacks the stripes of B. calamita or Pelobatus fuscus.
It is brown without the green colors of Alytes obstetricans.
A red yellow or red belly is not visible at the photos, but I assume you would have noticed it if it was present (ruling out ...