NavList:

Actually, there is one very well documented case of an accurate internal clock.  I'm a little surprised you missed it Frank

The honey bee (apis mellifera), upon return to the hive after finding a source of pollen and or nectar, will indicate to other worker bees in the hive how far the source is and in what direction relative to the sun it is.  The retort will be that the direction indicated will be instantaneous and fleeting in correctness.  It is well documented, however, that the angle indicated *changes* as a function of time, thus making the angle relative to the sun correct, even as the sun changes position in the sky.  The only way to do that is by some internal sense of the passage of time, since there are no documented cases of honey bee constructed chronometers.

Apis Mellifera also understands which hemisphere they were born in!  Using the above paragraph as a baseline, scientists checked if bees transported across the equator would indicate the time - angle as if in the new hemisphere or would insist on using the old hemisphere.  The bees did in fact persist with the old hemisphere, but only for about 6 weeks.  6 weeks, you see, is the lifespan of a worker bee.  Once the old timers died out, the new bees (very deliberate pun!) indicated the time angle for the new hemisphere.

Apis mellifera are quite sensitive to UV light, and in nature, the sun is a very bright source of UV.  There is decidedly *no doubt* that bees are using the position of the sun to navigate (the very definition of celestial navigation) and further, that they are accurately aware of the passage of time and how it will alter the angle and the navigation.

None of it, of course, is by careful thinking, applied mathematics, chronometers, calculators, slide rules or any of the other tools we use.  It's 100% instinctual.

Brad

On Dec 19, 2016 9:10 PM, "Frank Reed" <NoReply_FrankReed@fer3.com> wrote:

Bill Lionheart, you wrote:
"I was wondering how accurate animal's body clocks could and if any actually have a good sense of longitude."

Heh. That's an interesting thought! Animals with natural chronometers?! I would have to say that this may be beyond the pale of reasonable possibility. There's nothing even remotely approaching an accurate clock in the biological world without environmental cues. Are there any examples of organisms with diurnal rhythms as accurate as even 5% when lighting and other environmental cues are suppressed? Also, and equally critical, how would such a thing ever evolve? Evolution is generally believed to develop new senses and capabilities by co-opting changes that have developed for some other purpose. For example, feathers evolve for thermal control in dinosaurs and are then co-opted for flight in birds. But what could ever lead to a biological chronometer? What biological use is "half a chronometer" to twist a phrase...

You wondered:
"also any other evidence of more detailed knowledge of the night sky in animals. It struck me some whales travel a long way and not just North-South, and they have huge brains (so could remember a lot), wonder if they pop up to look at the sky for navigation? Maybe they cant see so well in air."

Hmm. Another interesting thought there. Could whales perhaps see the Southern Cross and use it for latitude? Maybe, just maybe... but it's an extraordinary claim and would require some extraordinary evidence. Instead of navigating by looking up, it's also worth considering that many whales could simply follow the trash on the ocean floor and navigate by looking down. They dive deep. A whale would make his way from one seafloor wreck to another navigating across the Pacific. You can imagine them passing along the route info... "when you see the Lockheed Electra with the female human bones in it, turn left".

Frank Reed