BIG MAMMAL TRAMPLES DEAD DINOSAUR! :-o

["dinotracker" <dinotracker@earthlink.net>]

BIG MAMMAL TRAMPLES DEAD DINOSAUR!  :-o

    Pardon that WEEKLY WORLD NEWS type headline.  Sorry, but it was just to
get this item the attention it merits.

    In the world of Early Cretaceous mammals, a BIG mammal does not mean the
same thing as it does today.  Yet by current paleontological knowledge, an
Early Cretaceous mammal that leaves a track 6.4 cm (2.5") long is undeniably
large.

    On Monday, June 17, 2002, at one of my most productive Early Cretaceous
dinosaur track sites here in the state of Maryland (USA), I found just such
a large mammal track.  It is likely the most important single track I have
ever found in this state, and those of you out there who have recently seen
the collection know that is 'really saying something'.  The track's digit I
impression closely resembles what might be produced by an opposable (or
quasi-opposable) thumb, making me wonder if it could be the track of a very
early marsupial.

    The track is marvelously pristine looking, possibly meaning it had
initially been overlaid by clay.  In fact it is almost as detailed and clean
as the fresh raccoon tracks I often see in the moist, fine sand at stream's
edge.  I have not determined for certain whether the track is the imprint of
a manus or of a pes, but favor the pes explanation for several reasons.
Whether by pes or manus, the track surely was made by the right side of the
animal.

    The claws were evidently fairly narrow and sharp, impressions of digital
pads are visible, as are impressions made by pads beneath the main body of
the foot.

    So, what is meant by, "TRAMPLES DEAD DINOSAUR"?

    Well, about 35% of the substrate shows patterns indistinguishable from
natural casts of dinosaur skin with which I am familiar.  That area shows
interlocking hexagonal and sub-hexagonal raised patterns (grooves between
them) of a character and size suggesting the cast of the skin of a fairly
good sized dinosaur.

    Playing 'the devil's advocate', one might reasonably ask how sure one
can be that these are not just hexagonal mud cracks.  For one thing, the
seeming skin cast is composed of sand grains conclusively too large to have
permitted hexagonal drying cracks around solid units of the 12 mm to 16 mm
size we see there.  Also, I have during my years of tracking in the Early
Cretaceous of Maryland picked up literally hundreds of thousands of pieces
of the same type substrate and none of them have ever shown hexagonal drying
cracks.

    One of the seeming  'tubercles', dermal ossicles, or whatever they might
be properly called, of hexagonal shape, appears to have been partially dug
out, as though by a claw, leaving a rim adjacent to the recessed outline
(division between the dermal ossicles).  I take this as one more evidence
that we are looking at a skin cast and certainly not an artifact of drying.

    In fact, the seeming skin cast part looks indistinguishable from some
unquestionable dinosaur skin cast I've seen.  The place where the track
occurs is slightly raised above the skin pattern, which it appears to
overlap, as though the skin had been partially covered by the wet sand on
which the mammal was heading away from the 'skin' area.  It is as though the
mammal had been walking across the probably decaying skin and maybe clawing
for a place to break beneath the skin in search of a meal.

    In the area where digit I has pressed the sand aside, I see some
smaller, much more shallow interlocking hexagonal skin patterns that may
have been exposed by the pressure and/or motion of the foot.

    It occurs to me that if what looks like a dinosaur skin cast is as it
seems, then the whole fossil -- although a bit early in time -- might be
taken as an appropriate symbol of the radiation of mammals after the
extinction of non-avian dinosaurs:  mammal waking over a very dead dinosaur!

    The find might be interpreted as the first 'graphic' evidence of a
mammal checking out a dead dinosaur for food.  We wouldn't be able to say
whether it walked away satisfied, however. I will say that the footprint is
nicely deep.  Could that mean it walked away with a full stomach?  :)

    Anyhow this ichnite is absolutely beautiful!

    So, who is most knowledgeable of Cretaceous mammals?  I'd like to show
this to those with good knowledgeable of Cretaceous mammal osteology, and/or
to those with knowledge of their very rare tracks.

    This is certainly the finest quality mesozoic mammal track I have ever
seen.  It is both deep and detailed!

    ...and I thought dinosaur tracks were my 'the cats meow'!  :)

    Ray Stanford

"You know my method.  It is founded upon the observance of trifles." --
Sherlock Holmes in The Boscombe Valley Mystery