Primer: Good Movie (I think?)

Primer poster

I was just reading the top 10 underrated scifi movies list that has been going around and noticed that their number one pick ‘Primer’ was available to view instantly on Netflix. It’s hard to beat instant and free so I thought I’d give it a shot.

It certainly was an interesting movie. The Maker-type atmosphere at the start got me interested and once their machine starts working it really gets catchy. Then things get a bit complex (to say the least). I’d like to say I figured the plot out with no problem but to tell the truth I got pretty lost by the end of the movie. If you haven’t seen it yet, it’s worth just watching it without knowing anything else and see what you can make of it.

If you’ve already seen it, then you really need to see this cool (amazingly stuffed with spoilers) Primer timeline analysis.

Timeline diagram of Primer

I’m still debating if it’s cool or just crazy that you can make a diagram like that from this movie. I’m leaning towards cool since time-traveling paradoxes are pretty neat (as long as they’re not deleting my great-great-grandparents or creating sentient AIs with genocidal tendencies and Schwarzeneggerian physiques). Interestingly, the whole movie only cost $7,000 with Shane Carruth (the guy who played Aaron [the nonbearded guy if you’re as bad at names as me]) writing, directing, producing (and obviously starring).

So if you’re at all intrigued by the diagram above then I’d recommend Primer (and staying away from that diagram until later).


Comments (1)


When Do Leatherback Turtles Migrate South?

ResearchBlogging.orgCover of volume 19 issue 2 Behavioral Ecology

I’ve had this blog a year and a half now and although I’ve had a good time, I’ve never really wrote about anything I’m actually (somewhat) knowledgeable. So I think I’ll do a few posts on leatherback turtles. I’m no turtle expert but I did spend a couple years working on their migration and movement. My first first-author paper just got officially published so I’ll start with that. <ego>It made the cover of Behavioral Ecology</ego> which isn’t really a big deal but I thought it was kind of cool. The paper was about leatherback turtles migrating from their summer feeding grounds near Nova Scotia to head down to wintering and nesting areas in the south. (If you don’t feel like reading all this, you could just skip to the pretty cool {at least to me} movie down at the bottom).

Map of Nova Scotian waters

First a little background. If you don’t know much about Nova Scotian geography, don’t feel too bad a lot of my relatives in Michigan were surprised when I told them I was in Canada but still south of them. Here’s a map for orientation. Leatherback turtles come up to Nova Scotian waters to eat jellyfish in the summer and then head back south to nest, mate and presumably avoid the cold waters. Leatherback turtles are pretty cool animals and I’ll probably do another post with more details on them later. For now, you just need to know they’re big animals reaching more than half a ton and their size, blubber and counter-current heat exchange allow them to maintain a high body temperature in cold waters almost like a warm-blooded animal.

So back to the paper, my coauthor Mike James has tagged a whole bunch of turtles now and we were curious if we could see any pattern in when they begin their migration. One problem was that unlike migratory birds it’s pretty hard to define when a turtle begins migrating. Luckily the state space models of Ian Jonsen provide a method to estimate turtle behavior as either foraging or transiting. By finding the last foraging in a season, we could have a pretty good idea of when the turtles began their migration.

Once we figured out when the turtles began their migration, we tried to figure out what might be triggering it. We guessed it would have something to do with colder temperatures or declining prey abundance. I could get temperature from satellite data but there isn’t an easy way to measure jellyfish (leatherback food) abundance. As a rough proxy, we used chlorophyll estimates from satellite images. As a side note, it’s really cool that NASA provides their data for free. Just to cover as many bases as possible, we threw position, day length, the North Atlantic Oscillation index, water depth and the sex and size of the turtle into the mix and stuck it all into a stats model. After a bit of calculating, the model came back predicting that the position of the turtle and temperature and chlorophyll of the water appear to correlate with departures.

Predicted departure of leatherback turtles

The biggest factor for predicting departure was the position of the turtle. Northern turtles appear to leave earlier than southern turtles and turtles around the longitude of Georges Bank (abundant shelf ecosystem) and Nova Scotia (the study area and lots of jellyfish) stay longer. The contour plot to the right shows the relative probability of departure from low (red) to high (yellow). The contour lines and dates show when we would expect 50% of the turtles in a region to depart. Knowing these dates could be pretty useful for conservation since regulations could be lifted after their departure.

Northern turtles leaving earlier was pretty much what we expected since northern waters get colder sooner. So it was pretty surprising when the model also predicted that turtles are actually more likely to leave when the water is warmer and greener. Now I’m not sure exactly why this is but one possible guess is that warmer chlorophyll-rich waters provide more nourishment sooner and allow turtles to head south earlier. Another possible explanation is that jellyfish population might decrease earlier since many jellyfish die off after reproducing and warmer waters and increased prey allow jellyfish to reproduce sooner. Of course, a final possibility is that the correlation is just a funny coincidence in the data but hopefully this is unlikely.

Inferred foraging locations of northern and southern leatherback turtles and departure tracks

Since turtles didn’t appear to be leaving when the water cooled off, why were they still leaving early from the north? One guess might be that turtles leave earlier from the north if they have farther to swim to their southern nesting grounds but the difference from the southern and northern foraging areas is only about 500 km. Since leatherbacks can easily swim 2 km/hr, they could cover this distance in 10 days or less but we observed differences of more than a month. Without temperature or distance to explain it, the disparity could possibly be related to some difference in habitat quality. Unfortunately this will remain just a hypothesis until we get a lot more data on jellyfish distribution and feeding rates. It is interesting to note that although many leatherbacks are still foraging in southern waters (blue dots in the figure to the right), no northern foraging turtle (red dots) has been observed moving into southern foraging grounds late in the season (red tracks).

Now that you made it through all that text, here’s a video I made of the turtles foraging, transiting and migrating (higher quality here). By the way, it costs quite a bit of work and money to get a transmitter on a leatherback so each one of those points is a good bit of work done by my coauthor Dr. James.

A couple extra interesting things to watch for are turtles hitting the Gulf Stream east of the continental shelf and being swept to the northeast and turtles getting stuck in the Bay of St. Lawrence (there used to be a channel between Cape Breton Island and mainland Nova Scotia but it was recently filled in with a causeway). See the map above if you need help finding those. Anyway, that movie’s pretty much the highlight of my thesis. I must have seen it several dozen times already but I still get a kick out of watching the turtles swim around.


Sherrill-Mix, S.A., James, M.C., Myers, R.A. (2007). Migration cues and timing in leatherback sea turtles. Behavioral Ecology, 19(2), 231-236. DOI: 10.1093/beheco/arm104


Comments (11)


10,000 BC Review

10,000 BC Poster

In another adventure in early morning cinema, we decided to go see 10,000 BC. I can report that there are definitely not large crowds in the theater at 10AM on Daylight’s Savings Time Sunday.

So I went into this expecting it to be pretty horrible (Rotten Tomatoes is giving it a 8%.) but I like the theme and wanted to see the CGI animals. Unfortunately, the whole thing seemed recycled from other movies and forced. They really wasted a good theme by not even bothering to accurately portray the animals or the history. That said it did keep me and the girlfriend mildly entertained (then again we still haven’t bought a TV so our entertainment criteria is pretty low).

The movie starts out with what I would assume is a fairly good guess at what life was like in 10,000 BC; huts, fire and hunter gatherers. After a few adventures, the characters reach another tribe of people who are just starting to grow their own crops. Again pretty accurate. 10,000 BC is right around when people are thought to have discovered agriculture. After a few more adventures, the history goes right out the window as the heroes run into a full fledged Egyptian culture complete with writing, pyramids, maps of the world and sailing ships. The movies takes one sentence to explain this anachronism as either aliens or Atlantis. This seemed pretty silly to me since we would definitely have archaeological records of such an advanced civilization. Why not just call it 2,000 BC? (Probably because they couldn’t have mammoths then.) As a final punch in the historical gut, the movie ends with the hero receiving a gift of seeds including corn. Pretty annoying (and completely unnecessary) since corn is from the Americas and would not reach the Old World for another 11,500 years. That’s about all I have to say about the history and the plot.

The movie had quite a few (I feel) bad movie making decisions. First right at the start of the movie, everyone decides to cover their faces in mud (a la Braveheart). I’m sure mud facial decorations were common in many ancient tribes but I really don’t think it’s the best idea when the audience is just being introduced to the characters. Then throughout the movie it continually flashes over to show an old witch doctor lady from the village. Besides her being pretty uncharismatic, I thought this was pretty unnecessary to the plot. (Yes I realize they were setting up the ending but I think the mammoth had that taken care of already). Also, the tribe talks in an assortment of phony accents. I saw in a preview/advertisement that the director wanted to do the whole thing in subtitles (a la Apocalypto). I like subtitles much more than dubbing in foreign flicks but since no one has any idea how they spoke 12,000 years ago this seemed kind of stupid. I guess funny accents were the next best thing for him. If you do watch the movie, I swear somewhere in the first part at the village someone is doing a Scarface impression. Let me know if you catch it too. Also, there was a huge amount of noisy pixels in some of the dark shots. I’ve never noticed this in a Hollywood movie before. Not sure why they’d let that through into the final copy.

Finally the part that let me down the most was the computer generated animals. We only get three types in this movie; mammoths, some sort of giant bird and a sabertooth tiger. The birds seemed animated well enough but you never get a real good look at them. The tiger seemed pretty good in the dark but in the light it really looked fake and didn’t seem to move quite right. Also contrary to what the poster would have you believe, the tiger gets about 45 seconds of screen time. The mammoths are in a lot of the movie and oddly enough are often shown galloping with two front feet in the air followed by two back feet. I’m no elephant expert but this looked completely phony to me so I decided to look through the literature once I got home and it looks like it is in fact completely phony (I’ll post about this tomorrow Update: here). Overall the CGI seemed about equivalent to a Discovery channel show which is sort of a let down when they’re supposed to be a highlight of a Hollywood movie.

Now after all those negatives, I do have to give it some credit. Despite all the shortcomings, I was entertained for the parts where I wasn’t groaning at the accents, history or biology. It’s not a horrible movie, it’s just not all that good.

Rating: 2 out of 5

Scott Sherrill-Mix, March 10th, 2007


Comments (4)



I browsing around the internets this morning and came across a few mentions of the movie Cloverfield. I vaguely remembered seeing the preview and thinking it looked interesting. But when I saw the Bad Astronomer (who seems to have a pretty good taste in movies) say it was (and I quote) AWESOME, that was enough for me. So I woke up Xiaofen and we headed off to the theater ($5 off if you go to the 10:15AM show).

After seeing it I have to agree, I really enjoyed it and I was on the edge of my seat through the whole thing. I definitely recommend Cloverfield (in the theater if possible). Just one caveat, it’s possible the camera work might disturb anyone with motion sickness although Xiaofen didn’t have any trouble and she gets car sick all the time. I had only seen the (cryptic) trailer and didn’t have any expectations going in and I think that helped so I’m going to leave it at that and follow Wil Wheaton’s example and leave my slightly more detailed analysis in the comments.

Oh if you’re like me and worry that the director is going to stick a little extra on after the credits, there is a little something but it’s not really worth waiting for (only a couple seconds of audio and I’ll link to it below).

Possible spoilers in the comments


Comments (5)