Fish don't have eyelids except sharks. Sharks have an "eyelid" known as a nictitating membrane. Note the way the nictitating memberane in Sharks work, it blinks from the bottom up, not top down (2.5 minute video):https://www.youtube.com/watch?v=RSji6mc61EsSome tetrapods have nictitating membranes like cats and birds in addition to regular external eyelids:https://ift.tt/2FNOjIY nictitating membrane, or third eyelid, is unique to vertebrates, although not found in all groups. In many species, it represents the principal mechanism of ocular cleansing. In birds, the external eyelids possess smooth muscle, and may close only during sleep. The nictitans, on the other hand, is operated by two striated muscles and is capable of extremely rapid sweeps across theAnimated gif showing nictitating membrane of a Great Gray Owl ocular surface to clear the cornea of debris. Ocular surface lubrication originates from two secretory glands. The lacrimal gland is situated in the inferior temporal quadrant associated with the more active lower eyelid, although in many species this gland is absent or rudimentary. Additionally, most birds, especially cormorants and falcons, have a second secretory gland called a Harderian gland located in the posterior and nasal aspect of the orbit associated with base of the nictitating membrane. In falcons, this secretory gland produces a viscous solution to moisten the cornea during the breathtaking stoops that are the falcon’s trademark. Although the composition of these secretions is not known, a compound such as hyaluronic acid would moisten the surface without the rapid evaporation seen with a more dilute tear film. Such a coating would maintain a smooth surface, but might pose other difficulties by collecting debris (Schwab and Maggs 2004).So did the fish ancestor of birds and mammals have no nicitating membranes or did these fish lose the membrane (except for the shark) only to re-evolve it and then add a regular external eyelid to boot?So what good is an eyelid with no eyelid muscles. Regular eyelids are an example of a "POOF" addition to make a fish into a bird or fish into a mammal. If one wishes to insist on common descent, eyelid muscles are an example of small scale miracles that needs to happen along the way of evolving a fish into a bird or mammal with eyelids and nictitating membranes.We have animals with eyelids and those without. An evolutionist can say there is some sort of transitional progression of animals from animals with eyelids to those without. But that's no proof whatsoever that common descent actually happened physically and/or that it happened naturally.As I said, I believe there ARE transitionals and a progression of forms, but many of the transitional features (like external eyelids) require miracles, and hence for common descent to work, it requires miracles of special creation!One may postulate the Creator could either work via a progression of miracles through time (OEC/Progressive Creation) or one set of creation event in a short span of time YLC/YEC/YFRC. The distinctions between the variety of creationist models is a separate issue, but the point is, it would appear new organs have to POOF onto the scene to make common descent feasible.PS[I'm invoking ARN Rule 9 and am banning people from this thread who are on my block list from participating. If they want to object to anything I say, they are welcome to start their own thread and run it according to their rules and say whatever is on their mind. They can even ban me from their threads!A list of people on my block list is here: https://ift.tt/2ODkH3D ] via /r/CreationEvolution https://ift.tt/2U67vuh
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