I heard someone on television refer to Lobsters as the “insects of the sea”. Lobsters have an exo-skeleton and I’m pretty sure six legs, does any scientist consider the lobster to be an insect or closely related to insects?
They are definitely not insects. 
They are crustaceans, though, so the link is there.
More specifically, lobsters fall under the subclass ‘malacostraca.’ Malacostraca typically have stalked eyes, and an abdomen having six appendage-bearing segments.
Thanks!
Yes, most consider them fairly closely related… certainly more closely than the lobsters are related to us or to, say, starfish or fish.
Lobsters are a part of the subphylum crustacea, animals with a crustlike shell… (most of them being referred to as shellfish, though I don’t know offhand if there are any members of crustacea that are land-dwelling.) Crustacea is a subset of the Arthropoda phylum, “jointed leg invertebrates.” Other major subsections of Arthropoda are the insects and the arachnids (spiders,) as well as the extinct trilobites.
It’s like “Chicken of the Sea.” Not literal.
Insects and crustaceans are all arthropods.
It’s quite common for some familiar crustaceans to be mistaken for insects – for example the woodlouse.
I have often noticed that small insects such as ants can fall off an edge of considerable distance in ratio to its size (an ant falling off a tree is like a human falling off a 10 story building) but they always seem unharmed. This childhood observation has continued and I am convinced that since ants are so small and weightless, the force of gravity is so weak that when they do fall, the impact is minimal and thus the ants are unharmed. I know this is against the law that a nickel and a piano can be dropped from a skycrapper and the force of gravity is the same since they will both land at the same time.
So why is it that small insects can survive, in ratio, to otherwise fatal falls by humans?
Well, the square/cube ratio has a lot to do with it.
Small creatures like ants have a surface area or cross section that is fairly great in proportion to their volume compared with any larger animals. Weight is proportional to volume (cube of size) while cross-section varies with the square of size.
And the strength necessary to survive an impact is generally dependent on the strength of the cross-section. So the smaller you are, the more easily you can survive the impact of a fall (force of impact being determined by weight times velocity at the moment of impact, assuming that the surface you fall on is strong enough to stop you instantly.)
Did that make sense? 
There are various species of land crabs (although these all have to return to water to reproduce), and (as Larry Mudd says) woodlice, which are able to complete their entire life cycle on land (they still do like it on the damp side though).
SoulSearching - there are a few factors at play with an ant’s survival of a large fall (although they are both related to the way that different physical effects scale up and down):
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Terminal velocity - in proportion to its mass, the surface area of an ant is quite high; they don’t fall as fast as a larger object because the air resistance slows them down (an ant and a brick would fall in exactly the same way in a vacuum though)
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Body mass - the ant simply doesn’t have much mass, so decelerating it rapidly (when it hits the ground) doesn’t generate the same kind of force that a larger body experiences.
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Structural strength - not everything scales up in the same way - a human-sized exact scale model of an ant would simply collapse and be crushed under its own weight, yet scaled down, it is incredibly durable - carapace strength is proportional to thickness, muscle strength is (roughly)proportional to cross-sectional area, weight/mass is proportional to volume
Double the size of an ant and you double the thickness of it’s skin, quadruple the strength of its muscles, but octuple its weight. (or something like that, anyway)
The “law” that you cite about a nickel and a piano is true in a vacuum. The ant doesn’t fall in a vacuum.
Air resistance is roughly (very roughly) proportional to cross sectional area which varies as the square of the dimensions. Weight, the attraction of gravity, varies according to the cube of the dimensions. So as the dimensions get smaller and smaller the ratio of the force of gravity(weight) to the air resistance gets smaller and smaller. To something the size of an ant, the air is quite thick.
I learned something here. I always (or, at least since my half-ass college biology education) thought that isopods (pillbugs, wood lice, sow bugs, roly polys) were a separate class from insects and crustaceans and that there were no terrestrial crustaceans. But now I find that they’re an order within the class of crustaceans. It’s surprising, though, because they look so different from a lobster, crab or shrimp. I wonder if anyone in the world eats isopods or if the ratio of exoskeleton to meat is too high.
Thanks! 
Over here we have several TV programs by a chap called ‘Hugh Fearnley-Whittingstall’. River-Cottage, Return to River Cottage and his first was ‘A Cook on the Wild Side’.
In one episode he cooked and ate woodlice. He stated that whilst they were not the tastiest things in the world and probably offered only little nutritional value, his biggest dissapointment was that they did not go pink when he cooked them
Why don’t ants fall in a vacuum? Do they float?
Is a woodlouse a rollypolly? I have long suspected that “rollypolly” might not be a scientific term. The fellas in Larry’s linked photo look like rollypollies, which indeed i always thought were insects.
Or is the rollypolly a completely different creature all together?
I’ve never heard woodlice called rollypollies, but there are numerous local names for them and it does seem to fit them. Pick up one of your rollypollies and turn it over - if it has six legs, it is an insect, if it has more, it is probably a woodlouse.
Sorry, not gonna happen. Fortunately I know a 6yr old girl who will be more than happy to do this for me and provide a complete report.
The term woodlouse can be applied to several different types. There are those that cannot roll (my favourite term for them was “Chuckie-pigs”) and those that can roll - Which I believe our American cousins call “Pill-Bugs”.
Indeed; I have both* types in my garden; the roll-up ones are much more rounded (like little armadilloes) and the non-rollers are more flattened (like little turtles), more leggy and faster on their feet.
*I suspect we’re talking about more than two different species here though.
Despite my reputation as a voracious gourmand and despite my curiosity, I have never yet eaten woodlice - if they were about the size of lobsters (like those so-called ‘living trilobites’ we had in that thread a week or so back), I’d be tempted.
The ones that roll up into a ball are pill bugs. The others, I think, are called sow bugs. Both are woodlice (woodlouses?)
It is worth mentioning that there are also such things as Pill Millipedes, which superficially resemble woodlice, although Oh Dear God! they can grow to a lightly larger size.
