We know a lot about the sexy bits of male cephalopods — ask about hectocotyl arms and spermatophores sometime — but would you be surprised to learn that we don’t know much at all about squid ladybits? Of course you wouldn’t.

I have never seen a paddlefish in the wild, although I’ve seen young adults and embryos in the lab — they are quiet, secretive beasts, cruising gape-jawed through our regional rivers to dine on plankton, and growing to immense size without ever troubling anyone. They are gloriously weird animals. But they are in danger of extinction because they also produce voluminous quantities of eggs, also known as caviar. A large female can carry $40,000 worth of eggs, so they are fished up, ignominiously slit open and disemboweled, and left to rot on the river bank.

It’s a real shame. Once again, we hunt a spectacular North American native species to extinction, all because of greed.

This could be bad. For years I’ve been hearing about the nightmare scenario of global ocean warming rising to a level that triggers the release of methane hydrates locked up deep in the ocean, which then lead to a major accumulation of greenhouse gases. It basically tips over the rate of warming from one regime into another, faster period of heating, very abruptly.

Well, guess what…

Vast methane plumes have been discovered boiling up from the seafloor of the Arctic ocean on the continental slope of the Laptev Sea by a dream team of international scientists. Over the last decade a warming tongue of Atlantic ocean water has been flowing along the Siberian Arctic ocean’s continental slope destabilizing methane ice, hypothesize the team of Swedish, Russian and American scientists. The research team will take a series of measurements across the Siberian seas to attempt to understand and quantify the methane release and predict the effect of this powerful greenhouse gas on global and Arctic warming. Because the Siberian Arctic contains vast stores of methane ices and organic carbon that may be perturbed by the warming waters and Arctic climate, Arctic ocean and Siberian sea methane release could accelerate and intensify Arctic and global warming.

It’s like humans are blithely giving the little nudges that start an avalanche, and then afterwards we’ll look at each other and say “I didn’t do it, it was deep ocean methane!” Or rather, we’ll try to say that while struggling to keep from drowning or cooking.

Our new residents are getting a bit cocky — they strolled up to my back door and were peering into our dining room. And then when I rapped on the window, they sucked their teeth at me and went about their business.

They may be plotting a takeover.

It’s been 25 years since Gould’s Wonderful Life: The Burgess Shale and the Nature of History crystallized the debate over the importance of contingency in evolution, most famously illustrated by his metaphor of “replaying the tape of life”. If we could roll back the history of life on earth and restart it in the pre-Cambrian, would we see the same forms arise again? Would we have dinosaurs a few hundred million years later, and bipedal intelligent apes after a half billion years?

Gould’s answer was no — that the role of chance was too great, and because the forms of life do not represent optimum ideals built by perfectly plastic forms, but rather are kludges built atop limiting and enabling prior adaptations. Some people, like Simon Conway Morris, argue otherwise that there are ideal forms (including us bipedal anthropoids) upon which life will tend to converge. I favor Gould’s view rather strongly — it’s absurd to talk about evolution without an appreciation that all organisms are the product of history, and that what traits we have now are almost entirely contingent on what traits our ancestors had.

My favorite example of the error of limited thinking about adaptive ideal forms is a comparison of bony fish and squid. Both are fast swimming, active predators that are torpedo shaped in motion (physics constrains that!), but in detail everything is completely different. If the pre-Cambrian ancestor of all chordates were accidentally squashed, there is no reason to assume that the pre-Cambrian ancestor of all molluscs would then evolve a line of torpedo-shaped predators with brainy skull at the front and an undulating muscular body for propulsion. Why should they? They have a demonstrated capacity in our universe to evolve into torpedo-shaped predators with tentacles at the front and propulsion via a jet of water squirted out of a muscular mantle cavity.

The body plan of the ancestor dictates what capacities the descendant will have. There is no reason to assume that the world as we see it now was inevitable — that’s simply a failure of imagination and reason.

An article by Zach Zorich explores other examples of evolutionary contingency. Much of it is dedicated to that fascinatingly concrete example of actually being able to roll back the tape of life, the Lenski experiments, in which populations can be frozen and restarted at any time. In that case we seen on a molecular level that the evolution of specific biochemical problems is not inevitable at all, but depends entirely on the presence of prior mutations. History, and your parents, matter!

But I also like this example.

“Not everything is possible,” no matter the process, Wake explains. “Organisms evolve within the framework of their inherited traits.” Organisms can’t pass on mutations that kill them or prevent them from reproducing. In the case of Hydromantes salamanders, their ancestors had to overcome a serious limitation: To acquire their ballistic tongues they had to lose their lungs. That’s because their tongue partly derives from muscles that their predecessors instead used to pump air into the lungs. Now, that formerly small and weak muscle is much larger and stronger. It wraps like a spring around a tapered bone at the back of the mouth, and when the muscle squeezes, the bone generates the force that fires the tongue along with its bones out of the mouth. So, Hydromantes’ ancestor did not simply acquire a mutation and evolve a fast ballistic tongue. Instead, the adaptation followed a series of mutations that first enabled the creature to overcome its reliance on lungs for oxygen and buoyancy control. Each change was contingent on the one before it.

Chameleons, on the other hand, retain their lungs. Instead of re-tooling their lung anatomy, they have evolved a piece of collagen that allows them to catapult their tongues at prey. On the surface, salamander and chameleon tongues converge, but not upon closer inspection. It takes a chameleon 20 milliseconds to shoot its tongue at its prey, a positively glacial pace when compared to the Hydromantes’ five-millisecond firing time. Why are chameleons stuck hunting with such slow tongues? The answer is that they have encountered a kind of obstacle to convergent evolution. The chameleon’s tongue is fast enough to ensure their survival, but they lack the “framework of inherited traits” to evolve the salamanders’ deadlier ballistic anatomy. The chameleons have reached what biologists call an “adaptive peak.”

Before anyone says that ballistic tongues represent an example of convergence, too, I’ll agree…but with the caveat that this is an example of modifying extant traits in the tetrapod toolkit. Two vertebrates evolved ballistic tongues, because they share the trait of having tongues. Squid also have a high speed prey capture mechanism, only lacking tongues, they use a pair of arms.

As D’Arcy Wentworth Thompson put it, “Everything is the way it is because of how it got that way.” You can’t appreciate evolution unless you also recognize the path it takes…it’s all about the trajectory.

If you’ve been following the world of Twitter (cue chorus of people who insist they’d never ever use stupid ol’ Twitter), you know that there’s been one of those epic corporate missteps: The CEO of Twitter, Dick Costolo, volunteered to answer questions sent to…a hashtag on Twitter, #askcostolo. What followed was amusingly voluminous, as the angry horde of Twitter users rose up as one to flood the hashtag with their anger at the incompetence of the company in providing tools to deal with abusers. As currently configured, Twitter makes it easy to sign up willy-nilly for anonymous accounts and for users to make racist and misogynistic threats without fear of punishment, or to create accounts solely for the purpose of stalking people online…and there are thousands of Dennis Markuzes out there, fulminating obsessively and hiding behind a flurry of throw-away accounts, all happily enabled by the mostly male engineers at Twitter.

And that’s the real problem, that Twitter won’t even take the basic steps of making it possible for users to block repeated harassers. It’s not clear why; it is clear that they don’t seem to think rape threats are actionable issues.

Anyway, one person made some simple suggestions for the least Twitter could do.

Block all users whose accounts are less than 30 days old

This is easy—it takes an arrow out of the quiver of serial harassers who use alternate accounts generated as needed.

Block all users whose follow counts are less than whatever threshold users set

Google used the social proof of “back links” to establish credibility and ranking for content over 16 years ago. This is old hat by now. Users should be able to block anyone who can’t convince other people to follow them.

Rings of followers created just to subvert this will have to be detected.

Again, hire a Google engineer. They’ve cracked this one.

Block new users whose @replies include any words the user decides

Users who are on the receiving end of harassment face startlingly unimaginative adversaries. The  same slurs and threats are used over and over. Brand new account with no followers using the n-word? Block!

That’s stupidly easy to express algorithmically.

Block any user who has been blocked by more than N people I’m following

Let’s also share the load. If all your friends block someone there’s a decent chance you’ll want to also.

Auto-blocks are opaque

There should be no feedback when a behavior triggers these measures. The harasser should believe that everything is working as normal.

The first two suggestions are a bit problematic in that there are easy ways to get around them: the obsessed stalkers will just build up a small population of sock puppet accounts that will also link merrily to each other. It’s a bit of work and requires long term planning, but really…that’s what these loons do. They also put up barriers to brand new users.

But the others…wow. Do you realize that Twitter lacks even the most basic functionality of enabling keyword filters? We’re talking 1990s technology here, and the brilliant minds at Twitter corporate are unable to grasp the concept. They also violate basic security concerns: if you are being harassed, and you block an account, the owner knows right away to switch to one of his backup sock puppets.

One example: If you follow @AngryBlackLady, who writes about reproductive justice and racism, you know that she has been harrassed nonstop for two years by a goon who makes new twitter accounts just about every day, specifically to dun her with racist slurs and misogynistic noise:

Some of the smartest ppl in tech work at twitter, yet they won't/can't fix the abuse problem. #askcostolo #assholster pic.twitter.com/mwePtNBSQ7

— Imani ABL (@AngryBlackLady) August 3, 2014

This is basic. This is easy. Any idiot could provide functionality that would reduce this problem. Twitter, apparently, only employs exceptional idiots.