Boo!

This is The Ghost of the Lone Male Excavator! I just wanted to drop in and announce that I have nothing paleontological to report. Also, I await the next blog post from Andrea ...rattle, rattle, rattle...
Aloha.

may the force be with ryan

Sad but true: our Lone Male Excavator has left us for more exotic locales (grad school in plant and soil sciences on OAHU) and we miss him already. Ryan has been a careful and conscientious excavator, a funny dude, a good friend, and last but not least, an incredibly snazzy dresser (plaid + camo = AWESOME).

Yes, we will miss his hard work, his dedication to replacing shoring boards in the heat of summer, and his enviable ability to reach things on tall shelves, but we will also miss his encyclopedic knowledge of all things Star Wars, his willingness to talk in funny voices for our amusement, and perhaps most of all...

his unparalleled ability to re-purpose old broken office furniture during his lunch break. The above photo may appear to be an ordinary office chair, but look closer! It is actually an office chair attached to another chair because it broke off its original base. The wooden legs of the base chair have been careful sawed at an angle for maximum comfort.

And what became of the base of the chair, you ask? BEHOLD:

This is quite possibly my favorite piece of furniture ever. It's an end table! On WHEELS! This handcrafted beauty is made of another chair (with the back sawed off) screwed onto the base of the broken office chair, with a piece of laminate for a top. And it's the perfect height for chips and salsa!

Finally, Ryan's coup de grace:

A genuinely well-made desk for volunteer Christina, made out of the side of box 10B (I think it's 10B).

In conclusion: Ryan is awesome! We totally miss him! He is funny and us taught about plants and how to sharpen tools and such! However, on the bright side: we now have a couch to sleep on when we go to Oahu...

Godspeed, Ryan, and may the force be with you.

Final Note From the Lone Male Excavator

Shore, -ing. (Verb):

the process of replacing old side-wall boards in large dug-out spaces (e.g., Pit 91).

This post will serve as both an introduction to some of the "other work" that excavators (and excavatrices) perform at Rancho La Brea and a documentation of the particular method of shoring board replacement that the Lone Male Excavator has developed.

So as the thick boards holding up the side walls of Pit 91 grow old, they often bow out, rot out, or both. Up above the pit, 14ft x 11 3/4" x 2 3/4" boards are stored ready to be cut to an average of about 75" long for use as a shoring board.

After a board is slated for replacement, of course it must be extracted. This is commonly far more difficult than it sounds. If the board is rotted to extremes on the ends locked in by the I-beams, then it is not too tough for a hatchet to cut through one end and pry the board out with a crowbar. If the board is not rotted away much at the ends, however, (as the boards pictured here) it can be quite difficult.

Initially, a cut with a circular saw is made through the board(s) being replaced. This is very dangerous and every safety precaution must be taken at this point (e.g., clean goggles, steady hands, hard hat). It is also messy and anything, including one self, which should not get covered in sawdust should be protected. If two parallel cuts, about 2" apart are made, extraction will be easier. Our cordless circular saw, however, does not cut deep enough to go through to the back of the boards.
So I have added to this method inspired by the wisdom of William A. Akersten's thought on sabertooth cat incisor (front teeth) functional morphology.

The points on large, cone-shaped incisors of Smilodon fatalis are separated to the extent that when they pinch together top to bottom and pierce into the skin of prey, they are thought to create a perforated line which allows for easy tearing off of chunks of flesh. When we are unable to pry/break out a board along the saw cuts, holes can be drilled along the cuts to create such perforated lines which can then be hacked trough easily or broken out through prying.Once a board is out, the wall of earth, often asphalt saturated, must be shaved a little with hand tools or, in dire need, a pneumatic chipper. Occasionally fossils are found in the side walls, so these must be watched for and documented when discovered.

Depending on the thickness of the new board and the bowing out of the old board shaving the walls may take up to a couple hours. Once this is done a measurement for the new board's length is taken, giving about an inch and a half behind the lip of each I-beam. (Often, when you think you've shaved enough and try to get the new board in, you find that a few spots need more shaving. The first of these two pictured here took me 3 attempts. I also found that I had cut it too long and had to take an inch off one end.)

After you've seen that the board will fit the space you've shaved out of the earth-wall, you must get it equally situated behind the lip of each I-beam... not so hard when you've got two-three boards out and you are doing the bottom board, but if you are trying to slide a single board over in a single space (like w/ the second board pictured) it can sometimes involve a long trial messing with crowbars. I have no solution, except putting in the lag screws early and trying to use them to slide the board. This does not often work.

If gaps are left, they are reduced by placing thin pieces of wood at the bottom of boards.

The boards are locked in between (and behind the lip of) I-beams which run about 40 ft under ground. As much of the board as possible is slid behind the inside of the I-beam before 5/16" holes are drilled beside the lip of the I-beam for 9/16" x 3 3/4" lag screws. The lag screws go through, what I'm gonna call, giant square washers which tighten the board flush to the I-beam. A thin, small piece of plywood is often needed between the shoring board and the giant square washer.

There you have it; Shoring 101. The final exam is getting a board replaced and not injuring yourself in the process.

So the Lone Male Excavator is off to grad school. This is my last day as an excavator at the Page Museum at Rancho La Brea, but I will still be around in spirit. (In fact don't be too surprised to see posts in the future by The Ghost of the Lone Male Excavator.)

Note from the Lone Male Excavator:

Y'all need to chime in and tell Andrea what a good job she is doing on this here blog a'ight!

We've got a lot done since my last post. Finished another box, matter-O'-fact (10A)! We've busted out them there scapulae from box 1 and got loads more dirt out to, eh.

Keep yer eyes open for a new "what is it" post coming soon!

-Ryan

Note from the Lone Male Excavator:

What is a fossil? One of our readers, "Duys" in Belgium recently reminded me of how one can determine a fossil and I thought it a good time to bring it up. I'll meet that idea in a round about way here:

The other day, I held the back door for a family visiting the museum. One of them was in a wheel-chair and since the back (staff) door is nearest the parking lot, could enter there. Anyway, I was heading into the lab and so held that door open too so that they could get a peek inside at Shelley and the volunteers eating lunch and glimpse behind the scenes fossil workstations. The older gentleman pushing the wheelchair asked me if I was a fossil... "I'm getting there," I replied. (Yes, the LME turns 30 in less than a month.) This question the gentleman asked was not one we get often, but we are very often asked if the bones and other previously living materials we dig out are, in fact, "fossils."

Strictly speaking, it depends on your definition of the word fossil. When I took Invertebrate Paleontology, my professor, in the first week, was discussing some common mistakes & misconceptions in word definitions. One he mentioned was archaeology vs. paleontology, between which this blogs readers surely already distinguish the differences and similarities (yes?). Another he discussed was the difference between "fossil remains" and "recent remains," as well as how to tell if what you have is a fossil. Being a geologist, he discussed the difference in whether or not the remains had undergone mineralization. He noted that a fossil will not smell if you hold fire to it. Furthermore, if you stick your tongue to a "recent" bone it will stick a bit, but it won't with a "fossil" bone.

Geologists and dinosaur paleontologists often use this sort of "mineralisation" definition, but how do La Brea bones hold up to it? Since they do still contain collagen, Rancho La Brea bones would, hypothetically, still produce a burning organic smell if we held them to fire. And, yes, ones tongue would likely stick to them if tried, but that may be more due to the asphalt than the collagen.

So I've decided to test these hypotheses with a personal experiment. (Of course, I am not serious.) We don't need to burn or lick these bones to determine that they have collagen, as studies have already used collagen samples from many of the bones in attempts to extract proteins and DNA.

So, are they not fossils?
A 30,000 year old bone is a fossil, no matter how you slice it. Ancient Rancho La Brea bones, plant, shells, and insect parts all fall under the more encompassing definition of fossil provided to us by thefreedictionary.com:
"A remnant or trace of an organism of a past geologic age, such as a skeleton or leaf imprint, embedded and preserved in the earth's crust."

The Rancholabrean North American Land Mammal Age (named for our site) spans from
300,000 to 11,000 years BP, so being of a past geologic age, our remains in this time frame are fossils.

Here is a question for you all:
Are the bones, plants, shells, insect parts, etc., that we find and can date to less than 11,000 YBP fossils? Pit 10 contained a vent of remains, for example, dated at around 9,000 years. So these are not technically from "a past geologic age." Are these bones not fossils?

Since Andrea alluded to it in a previous post, I have to mention that a month ago I sprained my left wrist when I rode the top of a ladder to the ground...backwards and downwards, and slam. I have missed my left hand terribly and promise to never take it for granted again if it works with me on the physical therapy and retains full functioning.
Lawyers need not contact me, as the staff here and NHM human resources department have been caring and accommodating.



Oh, and FYI:
We've completed excavation of Box/deposit 10B; our first box finished. It went pretty fast because it was a disturbed (mostly fallen apart) deposit and we did not measure out any bones or use a grid system on it. We will not, be changing the project name to Project 22, but the thought crossed our minds.

Note from the Lone Male Excavator:

Inspired by our friend Jack Tseng's "What is this?" post, I've decided to place here a mystery bone and you all have to guess what it is. The winner will receive a short on-site tour of the Project 23 excavation site, or, if you are a Page Museum volunteer and have no prior knowledge of what it is, you will win a hearty handshake from the LME (Lone Male Excavator).

I want a specific answer, should be two parts: what bone is it? & what species (or I'll take family) is it?
Ideally, you should also say whether it is a right or a left and what developmental stage it is in (roughly how old was the animal).

Note from the Lone Male Excavator

Hi all. I'm still here, treading in a sea of tar and estrogen.

In an attempt to be more like Andie, I've decided to put up another post and to start reading occasional comic graphic novels instead of just paleomammalogy and Harry Potter books, as has become the habit. I found this graphic novel of the first 10 comics of "Y, The Last Man" about this guy who ends up being the last man on Earth after all the rest die from something (don't know yet what, but I think it must be something to do with an attack on some phenotype from the Y chromosome, eh?).

Anyway, this guy is left alone in a world full of women, so I thought the series highly appropriate for me. We'll see.

Anyway, pulled this juvenile Smilodon vertebra out the other day (see pic). It is a very confused vertebra; it does not know whether it's an individual vertebra or part of the sacrum. This is a sort of developmental disorder likely caused by genetic problems and not uncommon in Smilodon. You can see (compared to the adult normal vertebra in the pic) that one side of the bone thinks it is a normal vertebra and the other thinks it is part of the sacrum. Furthermore, the neural spine is both off-center and angled wierd. I thought this one was pretty neato, but Michelle is the excavator, excuse me, excavatrix, who is really into pathologies.

This is one of the sweet perks to having such a large collection/set of deposits like Rancho La Brea: not only do we get a clear picture of the complete skeletal morphology of members of our fauna, but we get a very good knowledge of the pathologies which affected them.

Also see below the complete leaf I uncovered yesterday!

Note from the Lone Male Excavator:

I have often been asked what it is like to work as the lone man among four women. I usually reply in one of two ways. On a good day I say, "It is awesome to work with four talented, intelligent, beautiful, tough women." On a day when I am forced to watch The View and/or Oprah during break times I say, "There are good days and bad days." In essence each of my responses is true, but overall, I work with four people that know, as I do, that we have one of the coolest jobs on Earth. Though our tight-knit group is a socially intense and complex small band of hominins, it is this author's opinion that intragroup cooperation is facilitated quite readily by the composition of individuals and the male to female ratio.

Now, I'm sure you've heard enough on that matter for this post, and even if you have not, too bad, because I have something far more interesting to discuss:
We have partially uncovered the skull of a North American "Lion" (Panthera atrox). I'm sure that pictures will be posted of this find as we make more progress in removing the bones still above it and, finaly the skull itself. From what we have seen so far it is at least fairly well preserved. As was noted in an earlier post, we have also found a P. atrox pelvis. The skull was found in the same grid only a few inches below. We are curious as to how many of the many ribs and vertebrae and other bones found in this grid might also be attributable to P. atrox. Many of the bones in this grid have been of Smilodon [including a complete saber (upper canine)] and it is not always easy to determine an identification of the more general bones until they have been cleaned in the lab.

Well (2!), until next time...