The big five extinctions  are  regularly the subject of   many investigations, and speculations regarding the causes, the main  culprits  being  often put  down to  asteroid, or other  extra terrestial impacts.  Ongoing investigations  by  paleontologists,  together  with satellite surveillance,  continues to reveal, more and massive impacts ,   some   leaving  evidence  of 1000   mile diameter  crater rims.   And this  precludes  hidden underwater evidence  from the Pacific Ocean.

 Here`s a  brand new take on the subject.  Did  Earths Gravity  change,    perhaps  more than once,   via asteroids  , or   some other body  impacting,   and  concluding with  the  Earth,  ingesting  a  massive ultra dense,  Nickel  Iron   Planetary core  or cores. Such an object may have been orbiting the Solar System for thousands or even millions of years.

Following  a gravitational increase, which would in all probabilities,  be accompanied by  a reversal of  Earths  Magnetic Polarity,  long and far reaching  Gravitational  effects would ensue.  The pre-  nickel iron core ingestion  era,  of reduced gravity,  say of  I8 - 22 ft sec/sec  provides  answers to many puzzling   questions.  eg.  the  massive  sizes of prehistoric animals,  particularly those with outrageously extended necks,  that suggest a lower G factor.   A ,   G  factor,  increase,  explains the grounding of many birds that   previously flew,  albeit with smaller wings, and larger winged / high lift to body ratio hugh flying birds which suddenly could no longer accomplish long journeys, and were suddenly confined to modest sorties. together with the loss of  flying reptiles. Also, there is ;

The  sinking and entire loss of the Oceanic surface plankton types,  resulting in species loss of plankton feeders.    eg the Plankton Formentera, an species of fish that   sank to a lower oceanic level, effecting the entire predatory chain,   ie. a chain of life support obase upon,  who eats who, and where ?

One effect of  the G  plus.  effect  is that  the  everything was virtually twice as heavy.  Even the air.  The entire Earths water table was lowered temporarily,  water holes   would   swiftly  disappear for years,  until  Super  G  caused Earths Glaciers to accelerate their ice flows, raising sea levels.  Gravity is everywhere,  you can`t see it,   smell it or taste it, there is only one escape.    For the amphibious   that escape, is  displacement in water.   The shore dwellers survive,   as do the Caymens, Alligators and Crocodiles.
How can we prove or disprove,   a Gravitational Increase:  

Until now the  subject of  coprolite  (dinosaur faeces)   has been confined to  ascertaining the diet of dinosaurs. But now we have  three  entirely new questions. ( For Paleontologists , Mathmeticians, 
 and Dynamicists. )

1)  How long did specific faeces  take to fall ?

2) What was thwere velocity on impact with the ground.

3)  And at what rate did those faeces progressively deform, before they ceased motion.

Why ?  This is why .  This will tell us  an unexpected and surprising thing.  The afore mentioned questions, will when applied accurately to a sufficiently wide spectra of fossilised  faeces. eg or what was the Youngs Modulus ?

  Tell us the magnitude of Earths Gravitational Field  immediatly  prior  the extinction of the Dinosaurs 

That is  to say,  fossilied intact, impact deformed dinosaur faeces, and there pre impact deformation state,  are possessed of unique and important information,  concerning accelleration.   .(ie. G )

   Kevin Wilson