Facebook Ad Settings, Imagerial Discs, and Early Life

Today I Learned:
1) Facebook keeps track of what it thinks you're interested in, obviously, so that it can post ads to you that it thinks you'll be interested in. Well, today I learned that you can view and modify those stored preferences! You can find them under Settings, in the Ads tab on the left, then "edit" on "Ads based on my preferences", and I'm not going to give more detail about how to find it because that's the kind of thing Facebook changes all the time. You may be able to URL-hack your way there at "http://ift.tt/1ODtC09" It will show you a list of topics Facebook thinks you're interested in. You can delete and add (sorry, pun) interests as you want.

This seems like an awesome feature that Facebook should advertise more (again, sorry). Yeah, Facebook is going to give you ads, but you get to pick what stuff it shows you! You can, in fact, make Facebook's ads work for you and be relevant to you, and the beauty of it is that this is exactly what Facebook wants. Every ad Facebook shows you that annoys you lowers Facebook's profit. Every ad Facebook shows you that you go "oh hey, that's actually kind of cool" and click on is money in the bank for Facebook. So why don't they advertise ad customization more? Do they think their automated algorithms are better at finding you relevant things than you are? Or maybe they just don't have a great PR department or UI. Or maybe they don't want to mention it because they think people will be creeped out by Facebook keeping track of their interests.

...speaking of which, if, unlike me, you're creeped out by Facebook keeping track of your interests, this post is for you too. From the "ads" tab in settings, you can also delete all of your interests, if you like, and you can also disable the use of ads based on site usage (yeah, Facebook does that too) and automatic ad-like sharing of your social actions. Just be warned, based on Facebook's track record, you may need to re-set these from time to time, so if it's something you're interested in, I would recommend checking up on your settings every once in a while.

In the meantime, I was quite entertained by Facebook's list of my "interests". Here's a semi-curated list, with some commentary.

Amazon.com (no lie there)
University (makes sense)
Education (being a University lover, I can understand that)
Sales (???)
Student
IFTTT (I guess it's been reading my TILs)
NBC (....)
Facebook (Should Facebook really be advertising for Facebook on Facebook?)
Psychology
Biology
Internet
meme
HowStuffWorks (Yes, this is the kind of thing I want to see more of!)
Philosophy
Family
Friendship
Child
Love (For these last four... what human *isn't* at least somewhat interested in these?)
Cycling (uh no. I don't know how to ride a bike, Facebook. Nice try.)
Crying (ok, 1) what? 2) Why is this under "Fitness and wellness"?)
Coffee (again, fail)
Food (...what human *isn't* at least somewhat interested in this?)
Dogs (eh)
Gardening (Sort of, I don't do it though)
Millennium Falcon (This I can get behind. (BTW, it's classified under "Hobbies and Activities"))
Dance (Thanks a lot, Mengsha and Michael!)
Reading
Arts and Music
Son (...?)
Image
Fan
Concept (????)
Hogwarts
Republican Party (United States)
Democratic Party (United States)
Religion Rebel Alliance
Life Fictional Universe
(Not going to put it down here, but Facebook nailed exactly which phone model I have....)
Gmail users (yup, I tend to like those)
League of Legends (I've barely played, not sure where that's coming from)
NPR (yup)
Chewbacca (Ok, how the heck did it know that???)
i fucking love science (that explains why I get so many "i fucking love science" posts)
Bernie Sanders (interesting...)
George Takei (I'd vote for *him*)
Don McCullin (I don't know who that is)
Girls (band) (I don't know who that is)
Why? (American band) (I don't know who that is)
Cosmetics (?!?!)
Shopping and Fashion (?!?!?!?!?!)
Wand (?!?!... what?!?!?)
(five tags under "sports". It really doesn't even matter what they are, it's just hilarious that there were any)
Wait (system call) (Has facebook been profiling my software?!?! =P)

2) Imaginal discs are found in all insects! I'd previously heard of imaginal discs in the contexts of pupating caterpillars. In case you don't know, caterpillar metamorphosis is kind of creepy, quite mysterious, and really, really cool. Once ensconced in a cocoon, a caterpillar essentially melts into a goop of loose cells and nutrient broth, from which the butterfly is reformed whole. The caterpillar doesn't *completely* break down, though -- small clusters of cells, called imaginal discs, stay intact, and it's these clumps of tissue that form the seed for the new butterfly's organs.

Today I learned that imaginal discs are common to... I think all insects? They control development of insect body parts. In ants, for example, caste differentiation is driven at least in part by differences in regulation of the different imaginal discs to achieve different body plans. This goes some way toward explaining how butterfly metamorphosis evolved -- it's one of the more complex components to the metamorphosis, and this means that it would have already been present in the earliest proto-butterflies.

3) This one's going to be an unusual TIL in that it's not a fact. It's more a realization and a change of interpretation. Quick question -- when would you say was the birth of the modern land biome? Think about that for a little bit.

Before today, I probably would have said something like the Triassic (the first geologic period with dinosaurs), or maybe before then, sometime around when fungi evolved the ability to break down wood and we got the first carboniferous forests that we would recognize as forests, rather than giant piles of dead, unrotted wood covered in plants. Today I realized that a *lot* of the macroscopic life most important to our modern land biomes actually didn't evolve until the Cretaceous (the last age of the dinosaurs, a warm period lasting 80 million years, ending with the mass-extinction that offed the non-bird dinosaurs). The cretaceous saw the early evolution of birds(!), mammals(!!), eusocial insects(!!!), and flowering plants(!!!!). That's... really a lot of important groups, at least on land. It puts into perspective just how alien this planet was a hundred or two hundred million years ago -- no birds flitting from branch to branch, no bees buzzing from flower to flower and no flowers for bees to buzz between. Not a rat or mouse or vole or shrew. There might have been ants... but they weren't colonial yet. Just single ants, wandering about. No pollen allergies... because there was no pollen.

Sometimes I think that if you want to be a xenobiologist, you should study plants. Maybe archaeology would be just as good a substitute.

(Also, while double-checking facts for this fact, today I learned that in the Cretaceous, corals were not the dominant reef-builders on Earth -- check out rudists!)