28.12.08

brooding on my origins (origins part 1)

well i'm beginning to think that i'm not going to learn the identity of whoever bought me the plane ticket, for my 5th hatching day present, that has brought me back here to drumheller. whoever they are they've been going to great effort to lie low. so much so that no one else around here know about or even suspected i might show up.

now don't get me wrong, people of the web wide world, its been a fun trip home. however just some of the time. without anyone to specifically hangout with, its getting a little boring. as no one was expecting me to be here everyone is busy with work, and as the royal tyrrell museum is really busy i can't really tag along with anyone too long before i get in the way...

meaning i'm starting to get on everyone's nerves... that is till today when i made a fortuitous stop by the education department.

i popped up there on the hunt for anyone not currently working. i hit pay dirt, with my two former co-workers tony and yumi both on lunch break. one of the very rare times an educator at the museum gets to sit down and do nothing... even than their usually eating while preparing for the next program, tour, or hike of their day...

i was excited. this was going to mean i had someone to talk to/hang out with, if even for just a few minutes anyways. as cool a place as the museum is it can't really thrill or occupy you for days and days on end. so some social interaction was going to be a nice change for today.

at first it was a nice little chat about what tony and yumi had been up to throughout the day. a few dinosite tours (that's a guided tour to a real dinosaur bonebed), a excavate it (a simulated dig for the public), a couple fossil castings, and a kids day camp finishing off the afternoon. than suddenly the conversation turned to what i'd been doing...

that was a little awkward. i admitted to pretty much the same thing i'd been doing the last few days. bumming around the museum, and basically bugging anyone i found in the middle of a spare moment.

tony agreed. "yeah i'd been noticing that man," he observed, and than politely warned. "not that i personally mind, it's great seeing you around here again man, but some of the big wigs, well they're starting to get mad at you for reenacting the old days."

that wasn't good. i didn't want to strain my otherwise bad relations with the museum anymore. afterall making the people who fired you even madder wouldn't do me any favours. especially since the world museum community was a pretty small one...

than tony made a great suggestion. "what you need to do is find something that'll keep you out of trouble." he noted wisely. though a second later kinda undid the wise guy aura he'd built up. "though i'm not sure what?"

it was a great idea, but what could i do at the museum that i had never done before?... i mean i had lived here for two years afterall!

yumi made a suggestion that was a little obvious. "you could always use this as a chance to learn more about palaeontology," which i appreciated, but having gone through the galleries like a million times this week there wasn't much more i was going to learn in there.

just as i was about to politely ask her for a different idea, yumi put down one of the many books the ed department has and suggested. "you could start by looking up some stuff in one of these," she cheerfully advised. "even though i know lots, there's always more to learn, and i find at least one new fact in a book a day!"

well it sounded like a fine enough idea, and i saw no reason not to try it. however it wasn't going to keep me occupied all day, that alone for the next few weeks i was stuck in drum. with a brain as small as mine reading and learning can only go on so long before i get overwhelmed.

i worried that asking for another suggestion would hurt yumi's feelings, but i was going to have to ask for more... that was till i noticed the picture on the page yumi had just happened to open the book too. it was a picture of a dinosaur embryo in an egg.
_
suddenly i had one of those light bulbs turning on inside my brain moments! yumi was totally right. just not in a general sense like she had been talking in.

i'd always wanted to know where i'd come from, and why i was here in this the human world. now was the perfect chance to find out. where else but here at one of the top palaeontologic institutions in the world could i find out why i'd fossilized!!!

yumi and tony both had to run off to their various programs shortly thereafter, but i hardly noticed. i'd leapt full on into the education library... well okay i didn't actually leap. that would have damaged the books and probably me come to think of it... reading everything and anything i could about dinosaur eggs and nests. trying to find any references to vivus-fossils or my own egg's discovery.

i didn't find anything about me specifically, but i did learn a lot that i hadn't known before. you hear about dinosaur eggs all the time. yet at the same time beyond the fact that dinosaurs laid them and we find them i didn't know anything about them.

with this new knowledge added to that i'd gather back during my first look into my origins at the devil's coulee fossil nesting site i was starting to get a picture of how dinosaur eggs fossilized and were preserved into the present.

however being that i was at a museum with world class researchers on staff, who better to ask than the dinosaur egg expert just down the hall?!?
_
so i popped by the office of my old palaeontologist buddy dr. françois therrien, curator of dinosaur palaeoecology. his job is to look at anything and everything to do with how dinosaurs lived. whether that be their environment or them themselves.
_
françois was very welcoming when i showed up at his door with no appointment. he shook my hand when i came into his office, and of course like everyone else here in canada, wanted to know what i'd been doing with myself when i left. as for françois, he'd been really busy being a scientists and publishing tons of stuff while i was away.
_
with that out of the way i didn't want to waste his time and got to business. i wanted to know about dinosaur eggs. everything and anything he knew about them. which as luck would have it he knows a lot about. him and his research associate darla zelenitsky (who herself specializes on just dinosaur eggs... too bad she is based in calgary or i'd have double the experts!) have published a few papers on dinosaur eggs and nests in the last couple years.
_
françois was more than happy to not only share his immense knowledge, but even showed me some cool as specimens. like this nest, that was just in the news. he thinks it might be a dromaeosaurid nest.
_
man françois is the dude! totally dropping everything to help me out for an hour. without an appointment or anything! palaeontologists are the best...
_
that and he knows his stuff! i found out there was so much we do, and at the same time don't know about dinosaur eggs!!!

so the easiest way to relay this is through a...

okay, so to start off with dinosaurs, like our relatives the reptiles (our ancestors) and the birds (our descendants), have babies by, well, getting eggnant. which results in the mommies laying eggs, and the babies having to figure out a way to get out of them. which as i recall was a bit of a workout to say the least!
_
fossil eggs were actually discovered by science a lot earlier than most books tell you. for some reason the myth has developed that roy chapman andrews found the first dinosaur eggs in the 1920's, but this is NOT true. the first scientifically recognized dinosaur eggs were found in france in 1859, but as these were not as heavily publicized as those of andrews' they were overshadowed by the american museum of natural histories' heavy publicity of their find in the 20's.
_
since 1859 dinosaur eggs have been found on every continent except anarctica (more just because it is too cold in the present for people to properly wander around looking for fossils). don't let this world-wide coverage fool you though. there is a LOT we still don't know and need to find out about how dinosaurs laid their young...
_
one of the biggest gaps in our knowledge is who laid what. at moment we only have eggs from 1-2% of all known dinosaur types, and some of these eggs may be from types we haven't found proper fossils of either!
_
it can be (note i said can, not always!) impossible to be certain which dinosaur laid which egg due to there being no relation between a fossil skeleton and an egg. this is the same problem with linking dinosaur footprints to their maker. though we can guess at what soft tissue covered the bone we can not be certain, and thus even with close match of foot bones to footprints it can not be a sure thing.
_
unlike footprints though there is one sure way to link an egg to a family of dinosaur. that is finding an embryonic skeleton inside an egg (which is rare!). with the fossilized bones of a baby you can tell for sure whose egg it is, but this is the ONLY sure way to this.
_
in the past when egg sites were found to have adult bones of a dinosaur with the nest it was thought to be evidence of whose eggs these were. a famous case of this was roy chapman's eggs. they were found with protoceratops nearby, and assumed to be theirs. so that when the proper parents were found close to a similar nest it was thought to be stealing these eggs. so poor oviraptor got its name of egg thief due to misreading the fossil evidence.
_
most of the dinosaur eggs that have been found so far are from the end of the dinosaurs era in the later cretaceous. which seems odd. granted that's not to say no eggs have been found from the triassic or jurassic. there have been, but the majority are from the late cretaceous.
_
there are a number of theories on why this might be. it seems no coincidence that all of the dinosaur eggs so far found all have hard calcium shells. many palaeontologists believe this might show many dinosaur eggs didn't fossilize because they were a softer "leathery" eggshell.
_
environment changes going on in the late cretaceous may account for why more dinosaurs developed harder shells as time went on. at the same time there is no evidence to prove or disprove this, but it is an interesting suggestion.
_
the fact we have fossil eggs at all is extraordinary in and of itself though. when you think about an egg it is really just a thin shell, even if that shell is made of hard stuff. the fossil record has always been one of mostly hard things. so the more breakable or fall aparty you are the less likely you are to fossilize.
_
one of the other problems is that dinosaurs being land dwelling creatures, they tended to live in heavily vegetated places. well plants when they die and break down tend to make acid. though it is low enough to not usually effect bone (except in coal seams) egg shell being so thin would tend to dissolve if buried in such rocks.
_
only in environments that lacked this acid build up like the desert of cretaceous mongolia, or like the snail and clam rich deposits of devil's coulee above (note the eggshell in the centre of the pic and the snail shell right above it). these shells created an extra source of calcium that would buffer the shells and keep them from dissolving in the acid.
_
this also helps account for the rarity of dinosaur eggs. especially if not all of them were hard calcium but made of leathery shells instead!
_
from those dinosaur eggs we have found several different types of nesting and parental care have come to light.
_
immediately some dinosaurs clearly just dug a hole laid their eggs in it, and than left. leaving their babies to fend of themselves.
_
others such as this nest above showed more effort in the construction of the nest, and evidence the parents tended to the eggs at least until they hatched.
_
in this picture you can see how all the eggs have been arranged in a circular fashion which would have allowed a parent to sit on the top of the nest and keep them warm. something we call brooding in modern birds. in some dinosaurs care was placed into the laying arrangement, but due to the adults big size, vegetation was used to keep the eggs warm instead (otherwise the parent might crush their eggs!).
_
there have been some recent debates about how to interpret and detect a nest versus a hole. this makes sense as we are not finding the nest as it was made millions of years ago, but rather its buried remains. as nests are often buried by soils and sediment similar or identical to that which they are made of, seeing the before and after can be difficult to impossible.
_
there is a lot more specific detail i could try to tell you, but i don't get it all, and it's all about specific types of dinosaur eggs. since non of these are tyrannosaur eggs i'll finish here.
needless to say dinosaur eggs are an exciting and still wide open field of palaeontology!

now i have a lot more a base with which to try and figure out where and how my egg was preserved and than turned into a vivus-fossil i decided my next step talk to the one guy here at the museum who would know how my egg was found. than hopefully i'd have some answers!
_
to be continued... in the tale of three discoveries!

5 comments:

Dinorider d'Andoandor said...

NICE books!

Dr therrien looks younger than what I had imagined. My neurons are still more used to the Bob Baker type! LOL

I read that male dinosaurs may have helped mommies with that taking care of the eggs stuff.

BTW those Adocus eggs had a hard shell too. Do you remember?

Sean Craven said...

Hmmm... If they've found eggs from both saurischians and ornithischians and they all have hard shells that kinda makes it seem likely that all dinosaurs had hard-shelled eggs -- that hard-shelled eggs were produced by their common ancestors. I wonder when that whole thing got started?

And dude -- you may have a brain the size of a peanut but you're probably the most articulate five year-old I've ever heard of.

Raptor Lewis said...

Dude, you're WAY smarter than you give yourelf credit for. If you were stupid, than you wouldn't be able to write the Paleo Facts. Maybe Dr. Therrien can shed some light onto your mysterious past.

Anyway, if want something to do, you can read my blog. You will learn where my love of paleontology came from.

Dinorider d'Andoandor said...

Happy new year to all Zealandia's 5-year-old-tyrannosaurids named Traumador! .. and to his readers too! ;)

you will be my first friend receiving the new year! hope your wishes will come true.

Traumador said...

Dinorider- yeah francios is a young up and comer. i'd been at the tyrrell longer than him till i was fired LOL

as for males helping females there's a lot of debate on that. i wasn't going to go into the behaviour end of things as 99% of it there is no hard evidence for.

i do remember good old adocus (these pics and my actual visit with francios was THE day of the press release! we went from his office down to the gallery where he did a live TV interview with the specimen!!!)

Sean- now you have brought up a great point... and with what i presented that would be a logical conclusion (and it still is, but like always it's way more complicated). however i didn't give you the WHOLE story. sorry about that i will try not to shy away from the really technical stuff in the future. what with clever mammals like you putting me to task ;p

though both have hard shelled eggs in the fossil record, detailed surface anaylsis reveals that their egg shells at the microscopic level are very very different. so different in fact that they are used to TRY and general ID eggs from their shell makeup.

saurischians have less variation in their shell types than ornithischians as rule, but the theropods due have a lot of varation themselves. the ornithischians have over a dozen different egg shell compositions some of them quite drastically different.

due to this difference of shells in even the same general groups (minus sauropods and prosaurpods which due to their size needed to have hardshells through their whole history it seems) it can be argued (as it has been) that these hard shells evolved convergently, and that overall it was in response to environment changes we know were happening in the cretaceous.

at the same time there is debate, and many are in your camp of thinking. eggs are hard enough to fossilize at the best of times, and thus we may be getting a biasis of cretaceous eggs due to those new environmental factors perserving eggs better than before.

again a very neat field of palaeo that needs a lot of work!

Raptor- sadly francios wasn't able to help me with MY past, but his insights on eggs in general should come in handy!

as for your post its the next stop on the web i'm going to make!

Dinorider- cheers man. can't wait till you all catch up with me in the future :P