8 Awe-Inspiring Spiders

8 Awe-Inspiring Spiders


[♪ INTRO] When you hear the word spider, you might immediately
think venomous, terrifying, or just… nope. Or you could be like me, and think they’re
amazing! Very few spiders are actually harmful
to people, while lots of spiders, pretty much all of them, in fact,
are helpful to us in some way. When you look at spiders more closely, you
realize they have some amazing abilities that may lead to really useful things like tougher
fabrics or stickier glues. So in honour of these eight-legged creatures, here are eight spiders that
push the limits of biology. Net casting spiders in the family Deinopidae
are sometimes called ogre-faced spiders because of their two huge forward-facing eyes. In one species, these eyes can reach 1.4 millimetres
in diameter. And while might not sound big, that’s the
largest eye relative to body size found in spiders, about a tenth the length of their entire body. It would be like you having eyes bigger than
cantaloupes. These eyes give the spiders a wide but shallow view of the world, kind of like looking through a fisheye lens. They also contain lots of light receptor cells,
allowing them to pick up around 2000 times more light than the eyes of day-dwelling spiders
or humans. But seeing that much light during the day
is problematic, so they actually destroy parts of their retinas every day and rebuild them
again just before nightfall. These special eyes are what allow net-casting
spiders to, well, cast nets. Though they technically build webs, they don’t
use them like other web-builders do. Instead of making a big mesh net for a bug
to run into, they spin a small web between their legs. Then, in the dark of night, they drop down
on their prey from above and envelop them with their sticky net. Scientists think the spiders’ net casting
hunting technique, along with those massive eyes, evolved during the Cretaceous period
as a way to get prey that could now run. And now, they’re inspiring sensor designs. Since the spiders’ eyes are so good at picking
out targets and detecting motion in low light, engineers are hoping understanding
how they work can help develop sensors that do better in complex, dark environments. Pelican spiders are pretty easy to identify
even if you’re not an arachnologist. That’s because attached to their weird ballooning
heads are two menacing claws which, at rest, look kind of like
the bill of a certain water bird. Now, all spiders have these mouth-related
appendages, called chelicerae. They’re the parts tipped with fangs. But pelican spiders have evolved the
longest chelicerae of any spider, and they use them to ruthlessly
hunt their 8-legged cousins. First, a pelican spider has to find and creep
up on its target. So, it uses its legs to feel for web trails,
the long strands of silk that spiders leave to find their way back to their web, or draglines,
the stronger, outer edges of the web. This stalking process can take several hours. Then, when a tasty spider is within arms reach,
the pelican spider juts out its chelicerae at a 90 degree angle, impaling its victim
and delivering a fatal dose of venom. And that’s not the most gruesome part. The pelican spider will usually just
leave their prey hanging there, struggling around, for half a minute
or so until the venom has done its job. Despite their unique look, not a lot was known
about these spiders until recently. In January 2018, a biologist from
the Smithsonian Museum described 26 species of this spider,
including 18 new ones. And that’s helping scientists figure out
how pelican spiders’ unusual traits evolved and diversified over time. Darwin’s Bark Spiders spin webs that hold
not one, but two official Guinness World Records. They’ve got the largest webs because their
webs can be up to 2.8 metres across. And they’re the longest webs, too, because
their bridge lines, the tough strands which form the basis of the webs,
can be up to 25 metres long. Such uniquely big webs are
thanks to a special silk that’s the perfect combination of
strength and stretchiness. All spiders make the structural part of their
web from what’s called dragline silk, which has a protein core covered with a thin
sugary protein layer and a fatty outer coating. But the dragline silk from a Darwin’s Bark
Spider is two times more elastic than other spider silks and 10 times stronger than Kevlar. And that allows them to spin webs where other
spiders can’t: across rivers. Their oversized cobwebs span
waterways and grant them access to a bunch of flying insects
that other spiders can’t reach. And because of the strength of their webs,
they can even catch small vertebrates. Their super strong and stretchy silk may even
save human lives one day. Scientists are currently trying to figure
out exactly how the spiders make it in the hopes of creating a synthetic version, which
could lead to better bullet proof vests or other high-performance materials. The Mygalomorphae infraorder of spiders, which
includes tarantulas and trapdoor spiders, may have found the secret to a long life:
stay indoors and never change. Other spiders rarely make it more than a few years. But tarantulas can make it into their 20s, and Number
16, an unceremoniously named trapdoor spider, made it to the ripe old age of 43
before she died in October of 2016. Scientists think they live so long
because they spend their lives in stillness and solitude in underground burrows. Trapdoor spiders even seal themselves in with a
well-camouflaged door made of a cork-like material. And that means, a lot of the time, they just
kind of hang out in their home while they wait for a meal to come along. Staying in keeps them safe from most predators
and other threats, like dehydration. Their restful hunting style also means they
need to have a low resting metabolic rate. Their basic cellular workings need to be pretty
energy-efficient so they don’t burn through all of their fuel reserves before they can
stock up again. And there’s a theory that a low resting
metabolic rate means a longer life because using up energy creates damaging molecules called free radicals, so less energy use overall means
less damage to cells over time. Biologists don’t think that that’s the
whole story to their longevity, though. They’re still figuring out how metabolic rate,
free radicals, body size and aging all fit together. And that information could help them unlock
the secrets to longevity in people, too. This next spider takes prey capture to a whole
new level of weird. The spider family Scytodidae spit to immobilize
their meals. Most spiders make silk in glands at the rear
of their abdomens. But, when their prey is 2 centimeters or less
away, a spitting spider unleashes a spray of liquid silk from the
venom glands in its chelicerae. The spit is forced out thanks to a buildup
of pressure that comes from having large venom glands and a tiny muscle at the base of those
glands that squeezes when it’s time to fire. While spitting, the spider wiggles its chelicerae
from side to side at a rate of 1700 times a second
to spray a zig-zag pattern. And the silk becomes sticky when it comes
in contact with the air, pinning the prey down. This whole spit attack happens in
one seven-hundredth of a second. The spider can even regulate how much spit
it sprays depending on the prey’s size and how much its likely to struggle. Once its meal is firmly glued down, it will
sidle up and inject its prey with venom to fully immobilize it before actually eating
its meal. Scientists are still debating about whether
that initial spit contains venom that immobilizes the prey or if it’s just a kind of glue. On the one hand, the spit is made in venom
glands which have the ability to make both venom and sticky silk. But prey don’t look like poisoned when they
get shot, so the glands could be making silk
and venom at different times. And research to settle this debate isn’t
just to prove who’s right. Figuring out what’s actually in their sticky spray
could help engineers develop better adhesives. As you’ve probably heard before, brain size
isn’t everything when it comes to intelligence. That’s particularly true for the fringed
jumping spider, a spider with a brain the size of a sesame seed that plans and fine
tunes its strategy with every hunt. They’re found in parts of Australia and
Southeast Asia, and they have to use their smarts
to catch their prey, other spiders. They use what’s called aggressive mimicry,
kind of a wolf in sheep’s clothing approach. A fringed jumping spider might pluck the edge
of a spider’s web to create the exact same vibrations as a caught insect, for example. Or, it might hide itself in a leaf and vibrate
its body to mimic other species’ courtship displays. And which approach it takes doesn’t come
down to chance. The spiders can plan ahead
and change their strategy if an approach doesn’t work
the first time around. Scientists have shown their smarts in the lab too. These spiders can navigate and plan
routes through mazes, and they can find their way to a tasty snack after
only seeing the path briefly. They’ve also been known to use trial and
error to escape from a platform surrounded by water, rather than just using the same,
failing method each time. Some scientists think they developed such
smarts as a part of an evolutionary arms race between them and the spiders they eat. But the piece of the puzzle that’s missing is an
understanding of just how these clever spiders are able to do the things they can. Researchers are now studying their teeny brains in the hopes of learning more about
the neural basis for intelligence. Ponds and streams contain a lot of potential prey, if a spider if is willing to get their feet,
or rather their whole body, wet. And that’s why some spider species will
venture into the water on occasion, but there’s only one that lives almost exclusively underwater:
the diving bell spider. They can be found in slow moving streams, ponds
and swamps from Europe through central Asia. And they spend almost all of their lives below the surface, even though they can’t actually breathe water. Instead, they spin a special web between underwater
plants with three different types of silk fibers, and then drag air from the surface
to fill the space underneath it. Diving bells do all sorts of things in their
web-bubbles. They eat, sleep, and mate. And when they’re hungry, they can actually
swim around for a little bit in search of prey thanks to the fine, water repellent hairs
on their bodies. These hairs hold onto a little bit of air,
which acts like a scuba tank of sorts. You see, spiders breathe through small holes called spiracles on the underside of their
abdomens that connect to their lungs. As long as these holes are covered with air,
they can breathe, even if the rest of their body is submerged. And diving bells can tolerate lower levels
of oxygen than their kin, so they can swim out of their bubble homes
to grab a quick bite to eat without drowning. In fact, they’d probably live their entire
lives underwater, except the bubbles in their webs slowly shrink. So, once a day or so, they have to surface
and bring down a few batches of fresh air. And understanding how they create their little
bubble homes could lead to better materials for underwater use. Scientists are hoping analyzing the structure
of the different threads they use can help us make things that
stay glued when they get wet. You might have seen this last spider lurking
around your home, but you probably didn’t know it was
also an official world record holder. The giant house spider held the Guinness World
Record for fastest spider until 1987 when it was replaced by members of the arachnid
order Solifugae, and those aren’t true spiders, so I think it should have kept its title. Giant house spiders can run as fast as half
a meter per second, or 1.8 kilometers per hour. Which, OK, means it’s only about a tenth
as fast you are, but proportional to its size, that’s the same as you running 55 meters
a second. Giant house spiders run by alternating the
movement of their pairs of legs, two pairs stay on the ground and support
the body while the other two move forward. And their super fast speed largely comes from
having really long legs. Their leg span can reach as much as 10 centimeters. They likely developed such speed because they
don’t rely on sticky webs. Like other funnel-web spiders, giant house
spider webs are relatively flat with a funnel at one end that the spider hides in. And they aren’t sticky, so they just trip
things up a bit, and send vibrations to the spider
that alert them to a potential meal. The spiders then rush out to attack, using
venom to subdue their prey. Before you get too worried: that venom, while
deadly to bugs, is basically harmless to people. And try to keep in mind: if you see one of
these spiders running, it’s probably running away from you. In their eyes, you’re the scary creature. Since their legs are so important
for running to catch their food, house spiders can actually regrow them
if they get chopped off. And studying how they do that
could help us figure out how to grow our own organs or
limbs in the lab one day. Whether it’s building bridges across rivers
or solving puzzles, spiders are so much more than just annoying or spooky
creatures on the ceiling of your room. Many have smart or elaborate features that
allow them to do some pretty extraordinary things like spend a day underwater or destroy
and regrow their retinas. And by studying them, we might just learn
a few new tricks, too. Thanks for watching! If you liked this
episode on incredible arachnid abilities, you might like our list of 7 unbelievably hardcore ants. [♪ OUTRO]

What if all the Bees Die? | #aumsum

What if all the Bees Die? | #aumsum


It’s AumSum Time. What if all the Bees die? No ways. I will sell all my burgers and create a safe
house for them. That’s so cute Aumsum. There are more than 16,000 species of bees. Bees generally collect pollen and nectar from
flowers for their survival. In this process they help pollinate majority
of the fruits. And vegetable crops which are consumed in
the world today. Some studies reveal that more than 90% production
of cherries, blueberries. And almonds is a direct result of the pollination
efforts of bees. Also, certain bees have evolved as per the
size and structure of specific flowers. Hence if there are no bees, these plants would
definitely go extinct. This will also have a catastrophic effect
on the food chain. As the animals eating those plants will slowly
but surely perish. Finally, because of the absence of natural
sweetener like honey. Many people may switch over to an unhealthy
artificial sweetener like sugar. What if the earth was Cube-Shaped? Holy Moly. Will my cute chubby round face also turn into
a cube? Oh AumSum. Earth is spherical in shape because of Gravity. Earth’s gravity pulls everything equally towards
its center. And thus gives it a spherical shape. Now, if the earth was Cube-shaped. Firstly, it would look weird, right. Secondly, just like gravity. Our weight would be different at different
places on earth. This is because the 8 corners of the cube. Would be much further away from the cube’s
center. As compared to the rest of the cube. But this would be good news for people who
are over-weight and lazy. Now they can just go to the corners and voilaaa,
their weight gets reduced. Thirdly, due to low gravitational force. The cube corners would have very less atmospheric
cover & almost no water. Thus rendering them inhospitable. What if the Earth had 2 Moons? So What. Even I have my 2 lollipops, I lick them every
day. That’s gross AumSum. The most obvious effect of 2 moons would be
that. Our nights would be much much brighter. That would certainly be bad news for stargazers
and astronomers. Also, as you all know that tides on earth
are a result of the moon. So, 2 moons would either amplify this effect
or cancel out each other. If they were to amplify then we could have
huge tides. Effectively making living near shorelines
almost impossible. But it will definitely be good news for all
the surfers. Finally, as the number of moons increases,
so will the number of solar eclipses. Also, hypothetically, if they were to ever
collide with each other. Then the amount of debris coming out of such
collision. Would make living on earth almost impossible. What if Earth Stopped Spinning? It would gain weight. No AumSum. The Earth spins at a speed of 1000 miles-per-hour. Its atmosphere also moves along with it at
a constant speed. If the earth stops spinning suddenly, the
atmosphere would still be in motion. Sending everything on the earth’s surface,
flying into the atmosphere. Now, earth’s spinning generates a centrifugal
force. Which is responsible for the huge bulge of
water around the equator. No spinning means no centrifugal force. This water would migrate towards the poles,
where gravity is the strongest. Leaving behind a giant landmass. Also, remember that, even though the earth
stops spinning. It is still revolving around the sun. This means, we would experience a 6-month
day, followed by 6-month night. Some experts also believe that earth’s rotation
generates its magnetic field. Without rotation, there would be no magnetic
field. To protect us from the harmful solar winds. Making it extremely difficult to survive.

Are There Dead Wasps In Figs? | Gross Science


Figs are one of my favorite foods. They’re sweet and floral, and there’s something
about the texture that I find so delightful—the outside is soft, but the seeds in the middle
give you this totally satisfying crunch. But it turns out that many species of figs
contain the bodies of dead wasps. I’m Anna and this is Gross Science. Figs aren’t exactly your typical fruit. You can think of them as packages that contain
all of the fig tree’s flowers within them. But if the flowers are trapped inside the
fig how do they get pollinated? Well, that’s where fig wasps come in. In most species, pregnant female fig wasps
carrying pollen are attracted to young figs. They enter through a tiny opening at the fig’s
bottom that’s highly selective—it usually only lets in the exact species of wasps that
pollinate it. But, even the pollinators have a hard time
getting in. Most lose their wings and antennae in the
process. The wasp’s goal is to find a home for her
babies. And the perfect home is inside the fig’s
female flowers—those are the ones that would produce seeds if they were fertilized. So, the mama wasp drops a fertilized egg inside
as many of the female flowers as she can—sometimes, up to a few hundred. But she can’t get to all of them. Along the way, she winds up fertilizing the
rest of the flowers with the fig pollen she’s carrying, and those flowers begin developing
seeds. Once the wasp is finished laying eggs, she
usually dies inside the fig. Each baby wasp begins to grow, encased in
a protective structure that the plant forms called a gall. The male wasps mature first. When they emerge, they find the galls of the
female wasps, many of whom are their sisters, poke inside, and impregnate them before they’ve
even hatched! Then, the males die inside the fig, but not
before boring tiny holes through the fig’s skin. When the females do emerge, the fig has just
started producing pollen. The female wasps pick up some of that pollen
before making their way through the holes their brothers drilled, and go off to find
a new fig to start the cycle again. But the story’s not over. At this point, our fig’s seeds are finally
mature and ready to be planted. And that happens when the ripe fig is eaten
by animals, which poop out the seeds, spreading fig plants far and wide. Of course, humans eat figs, too. So, when you bite into a fig are you actually
eating the bodies of dead wasps? Well, if you’re getting your figs from the
supermarket, then most likely not. See, humans and figs have a really long history—we’ve
probably been domesticating them for over 11,000 years. So, while there are over 750 species in the
world, most of the figs we eat are a species called the “common fig,” which humans
have had a huge hand in creating. In fact, some common figs are seedless and
don’t require pollination at all. Other varieties of common fig do need to be
pollinated, but have separate male and female trees, and we only eat fruits from the female
ones. I’ll put a link in the description to a
great explanation of how common fig pollination happens, but long story short, female wasps
can only manage to lay eggs in the the figs from male trees, not female ones. But they can’t tell the difference between
the two types of trees. So, if a wasp does enter a female fruit, she’ll
pollinate it, and either manage to escape or die inside the fig. And then that fig might make it to your table. Frankly, one wasp here and there isn’t enough
to deter me from eating these things. But if you’re still feeling squeamish, just
think about it this way: by eating that fig, you’re benefitting from a complex and in my
view, beautiful partnership—or, what’s called a “mutualism”— between two very
different species. One that’s been delicately crafted by around
90 million years of evolution. And that certainly whets my appetite—at
least for curiosity, if not for dinner. MMMM! But also ew.

Licking bees and pulping trees: The reign of a wasp queen – Kenny Coogan

Licking bees and pulping trees: The reign of a wasp queen – Kenny Coogan


As the April sun rises
on a pile of firewood, something royal stirs inside. This wasp queen is one of thousands
who mated in late autumn and hibernated through the winter. Now she emerges into the spring air
to begin her reign. Most of her sisters weren’t so lucky. While hibernating in compost piles
and underground burrows, many sleeping queens
were eaten by spiders. Warm winters caused by climate change
led other queens to emerge early, only to find there was no available food. And some queens that survived the winter
fell victim to the threats of spring, such as carnivorous plants, birds,
and manmade pesticides. Our queen is the lone survivor
of her old hive, and now, she must become
the foundress of a new one. But first, breakfast. The queen heads for a citrus grove
full of honeybee hives. The bees can be dangerous if provoked, but right now they’re paralyzed
by the morning cold. Their hairy bodies are dripping
with sugar water from an earlier feeding, and the resourceful queen
licks them for a morning snack. Newly energized, our queen searches
for a safe nesting area. This tree hollow, safe from rain, wind,
and predators, is ideal. She chews the surrounding wood
and plant fibers to make a paper-like pulp. Then she builds around 50 brood cells
that comprise the beginning of her nest. Using sperm stored from last fall, the queen lays a fertilized egg
into each cell, producing as many as 12 in 20 minutes. Within a week,
these will hatch into female larva. But until then, the queen must hunt down
smaller insects to feed her brood, all while expanding the hive, laying eggs,
and defending against intruders. Fortunately, our queen is well prepared. Unlike bees, wasps can sting as many times
as they need to. With such a busy schedule,
the queen barely has time to feed herself. Luckily, she doesn’t have to. When she feeds an insect to her grubs, they digest the bug into a sugary
substance that sustains their mother. By the end of July, these first larva
have matured into adult workers, ready to take on foraging,
building, and defense. The queen can now lay eggs full-time, sustaining herself on her worker’s spoils
and their unfertilized eggs. Although each worker only lives
for roughly 3 weeks, the queen’s continuous egg-laying
swells their ranks. In just one summer,
the nest reaches the size of a basketball, supporting thousands of workers. Such a large population needs to eat, and the nearby garden
provides a veritable buffet. As the swarm descends,
alarmed humans try to swat them. They even fight back with pesticides
that purposefully poison wasps, and inadvertently impact
a wide-range of local wildlife. But the wasps are actually vital
to this ecosystem. Sitting at the top
of the local invertebrate food chain, these insects keep spiders, mites,
and centipedes, in check. Wasps consume crop-eating insects, making them particularly helpful
for farms and gardens. They even pollinate fruits and vegetables, and help winemakers
by biting into their grapes and jump-starting fermentation. This feast continues until autumn,
when the foundress changes course. She begins grooming some eggs
into a new generation of queens, while also laying unfertilized eggs that will mature into reproductive males
called drones. This new crop of queens and males
requires more food. But with summer over,
the usual sources run dry, and the foraging wasps
start taking more aggressive risks. By September,
the hive’s organization deteriorates. Hungry workers no longer clean the nest
and various scavengers move in. Just when it seems
the hive can no longer sustain itself, the fertile queens and their drones
depart in a massive swarm. As the days grow colder,
the workers starve, and our queen
reaches the end of her lifespan. But above, a swarm of reproductive wasps
has successfully mated. The males die off shortly after, but the newly fertilized queens are ready
to find shelter for their long sleep. And this woodpile looks like
the perfect place to spend the winter.

Extracting Spider/Bacteria DNA Using Columns – Spider Silk Step 1


This video is sponsored by
The Great Courses Plus Doing biology work is a lot like cooking You’re always following a recipe
but there are countless potential tweaks and variations you can make
to change the final outcome With biology every technique
has half a dozen variations And the ingredients are made by
dozens of manufacturers each with their own custom blends
of compounds for the task at hand Think of biological reagents like
barbecue sauce A recipe may just call for barbecue sauce
but there are dozens of brands and flavors and your choice can play
a big role in how the final dish tastes So, most lab work requires some knowledge of which protocol variations and particular products work for your specific experiment Take electrophoresis for example Using the same basic recipe you can perform
all of these different blotting experiments on a huge assortment of molecules or with PCR there’s likely
dozens of different types based on the DNA source and
what you’re trying to do to it As well as a ton of other subtle factors What usually ends up happening
is you shop around look at all the different
products and protocols and see if you can find one that
says it does the thing you’re trying to do Then you order those supplies,
try it out, and see what happens. Maybe it works right off the bat but often you’ll end up having to
try a couple others before you find one that gives you good results Today we’re going to look at
one central recipe And some of the variations we’ve
been using over the past few months If you’ve been following along,
you’ll know that we’re working on engineering a strain of yeast
to produce spider silk One of the first steps in that process is
getting some DNA out of the spiders so we can isolate
the silk gene itself This has proven to be
a nightmare and to date, I’ve used almost a dozen spiders
in various attempts So today we’re going to explore and compare
successful DNA extraction procedures for two different DNA sources Some bacteria And the spiders Before we go further let’s go over the basic
cake recipe before we talk about flavours we’ll be using a column based approach which tends to give better results than the shot glass
and alcohol method you may have seen before It’s not to say that
that can’t work but this method is more gentle and keeps the DNA intact better as well as being
standard lab procedure there are also other variations,
like bead-based methods and we’ll look at some of those
in future videos All of these extractions work
on a similar series of steps First, we get the thing we want to
extract DNA from and make it into a sort of paste
and add a salty, soapy solution to it this pops open all the cells so that the
DNA is floating around in the salty water we then remove as much of the debris as we can be it bits of broken cells,
or a leg, or whatever else This is done using a centrifuge, and all the
heavy debris will sink to the bottom We then take our clean solution
and load it into this special tube It’s basically the world’s
smallest coffee filter and the filter, in this case, is either
made of silica or a special resin we load the tube into a larger tube which will act as our collection cup and then spin it in the centrifuge to
pull the liquid through the filter DNA is negatively charged and in
the salty conditions of the solution the silica or resin becomes positively charged so the two stick together when we spin down the column the rest of the solution containing everything
else just passes right through we then do a series of washes
to clean everything and then we’re ready to collect the DNA we transfer the filter to a clean tube and then add a small amount
of either sterile, distilled water or various other solutions so long as they’re not salty without the salt, the silica’s charges
get hidden and the DNA falls off this time when we spin everything down we end up with a tiny amount of
concentrated DNA solution most of the time when you do
this you buy all the tubes as a kit that come with all the different
solutions you’ll need the manufacturers tune the solutions in
each kit to work for their particular application so if you try to mix and match,
your results can be pretty poor right now I have two different kits and I even tried mixing up my own solutions
though that didn’t work very well Let’s start with the bacterial kit This one is made to isolate plasmids which are small circles of DNA that we
add to bacteria to make them do new things sort of like putting a CD into a computer in this case I grew some E. coli that have a
plasmid in them that makes them bioluminesce but this should work regardless
of what the exact plasmid is the plasmid uses tetracycline
as the selection agent so I prepared 1 milliliter of LB broth with 10 micrograms per milliliter of tetracycline and innoculated it with some bacteria
and let it grow overnight on the day of the extraction I first spun down this liquid
to collect all the bacteria into a little pellet at the bottom the LB was removed and then it was on to the
various buffers and solutions in the kit The kit just labels things like
“PD1” “PD2” and “W1” which doesn’t really tell you what’s going on but I was able to find some more info online PD1 contains an enzyme called RNAse which, as the name implies,
destroys RNA this is to make sure you only isolate DNA PD2 is what’s called a Lysis buffer basically, it’s very salty, and contains a
special soap or surfactant in this case SDS as well as an enzyme, called Lysozyme which eats bacterial cell walls the salt makes the bactera shrink,
the enzyme eats away at the structual integrity of the bacteria and since cells are basically living bubbles of oil the soap makes them all pop open and whatever was contained inside is released into the solution you add both of these to your bacterial pellet and then re-suspend the bacteria
and let it sit for a few minutes so it has some time to work Once it’s done we add PD3 Which seems to crash out all the
proteins and debris from the solution making it go cloudy We spin this down, which collects all the floating
junk at the bottom, leaving our DNA in solution then we carefully pipette
off the upper liquid called the supernatant and run it through the filter using the centrifuge After it’s been run through the column
we wash the filter with wash buffer which contains a large amount of alcohol
to help remove any stubborn organics we then spin the filter while
it’s empty for a few minutes to dry it so all the ethanol is gone
before we elute the DNA For the elution, we add 50 microliters of
sterile water or elution buffer since the kit comes with that Rather than spinning it down immediately, we wait five to 10 minutes to give
the DNA time to release from the filter I’ve left columns for half an hour or more
if I really want the DNA to come off Then we spin it down to collect our sample You can actually run a second
batch of elution buffer through or collect the first batch and run
it through again to try and squeeze out
every last bit of DNA But that’s it, and the extraction is complete It’s pretty slow because of all the
waiting for things to spin but it can be done in less than an hour
once you get a rhythm going As I mentioned earlier, there are some
other variants of this same basic protocol and some forego the columns and instead you magnetic beads coated
in either silica or the resin Replacing some of the centrifuge steps with beads
can really speed this up That’s why I was working
on making some of my own I actually just got the supplies to make more So expect some tests of those soon Now, let’s compare to the spiders I actually tried running a spider through the bacteria kit and it failed as spectacularly as you might imagine The reason is because the solutions
are tuned to solve a different set of problems First, lysozyme, the enzyme in the bacteria kit
only affects components of bacterial cell walls So the much more robust spider cell walls
and clumpy proteins were unaffected On top of that, the spiders are full of
natural inhibitors and other enzymes that are still active So when you pop open any of the cells they can wreak havoc and destroy any
good DNA you manage to get out So I picked up a special insect/arthropod kit which addresses all of this It’s a 27 step procedure and some of these steps loop
or have long incubation times When I did this I started at 5pm
and didn’t finish until 11:30 not time efficient by any means
but if it works, it works First up, it only wanted 30 milligrams of tissue Which is about a third of a spider This may not seem like a lot, but
it’ll give plenty of DNA to work with I chose part of the dorsal side of the abdomen As it’s high enough enough to not touch the silk glands and make a mess but also contains lots of soft tissue this was suspended in CTL buffer and I used a P1000 tip to grind the tissue
and disperse it in the solution in this kit, this is the lysis buffer but instead of SDS as their soap
they use a cationic surfactant called CTAB Then I added an enzyme called Proteinase K As a protease, its job is to break down proteins And since spiders are chock full of them
it’s got its work cut out for it To speed things along the tube was put into a heat block set to 60 degrees Celsius This is the longest part of this process and can take anywhere from 30 minutes to 4 hours Before putting it in, the solution was murky and opaque but after two hours it had fully cleared which is the stopping point To really clean things up, the kit says to add a 24:1 mixture of chloroform and isoamyl alcohol Neither of which come in the kit So I made some chloroform and sourced the isoamyl What this will do is collect any non-polar debris as well as twist proteins inside out and move them out of the aqueous layer After giving everything a gentile mix The tube is spun down and
you end up with a layer of debris at the interface between
the water and chloroform I ended up making a stack of stuff so I could get this at eye level to make it easier Not great lab practice but I wanted good results The top aqueous layer is transferred to a fresh, sterile 1.5 milliliter tube for further processing Being careful not to disturb the debris To our now clean solution we add
some RNAse A and HBC buffer and incubate at 70 degrees Celsius for 10 minutes This will destroy any RNA while also deactivating any proteins that stuck around then we add ethanol before loading into the same sort of filter and tube setup as before However in this case the kit says their
filters are resin-based not silica based which I thought was interesting After spinning that down, it’s on to a series
of washes with the provided wash buffer And finally after all that we can dry the column by spinning it empty for a few minutes Transfer it to a final collection
tube and elute our DNA Again, letting it rehydrate for a few minutes beforehand As you can see it’s still the same basic process
but because of the tough tissue sample extra steps and ingredients were
needed to get the best results Speaking of the results, there are two ways to analyze your sample once the extraction is done Run it on a gel, which we’ve
discussed in two previous videos Or test it with a special spectrometer Personally, I like using a gel better Not only is it vastly cheaper, since we dye the DNA with a stain that really only sticks to DNA It’s much harder to get a false positive
which actually happened during an earlier spider extract The spectrometer said we had hundreds of nanograms of DNA But when we ran it on a gel,
there was clearly no DNA present This is because the spectrometer can easily be set off by protein or other chemical contaminants left over from the extraction We’ve since run both samples on a gel and we finally got lots of DNA out of the bacteria and spiders We actually saw the bacterial
result in the gel dock video But there’s a problem with the spiders In theory we’re supposed to be isolating genomic DNA which is huge strands of DNA As we discussed in the gel electrophoresis video this should look like a nice
band near the top of the gel But the spider DNA looks like a smear low on the gel, which means its highly damaged and most of what we isolated is
shredded DNA fragments This actually matches up with an earlier result where we managed to get a whiff of spider DNA but at the time assumed it had just been damaged by the extraction protocol Now the running hypothesis is that the ethanol preserved the spiders and prevents them from rotting But it doesn’t stop the spiders native
enzymes from destroying the DNA And this kind of makes sense When I cut into the spiders they
were mush on the inside meaning everything was damaged So now I’m looking to source fresher spiders. I’ve already got a few leads, so
hopefully some of them will turn out As a last resort, we may switch to another spider species because they’re easier to get But for now I want to see if we
can get the widows to work At least now we know that this kit works so as soon as we have a fresher specimen we can definitely move forward but other than that, those are all the basics of DNA extraction using columns Depending on the style and exact kit the amount of time it takes can vary, but
it’s never really a difficult process It mostly involves planning in advance, getting the right tools, and following the recipe Before we wrap up this is actually a great moment to talk about the
sponsor of this video: The Great Courses Plus Many of you have been asking how to get started learning the basics of biology, and The Great Courses Plus is a good place to do that. It’s a subscription, on-demand video learning service with top-notch lectures and courses
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start your free trial today To close out I once again want to take
a moment to talk about Nerd Thunder Which is an opportunity for science and maker channels to do some cross-promotion This time the channel I think you should check out is:
NileRed I know some of you already watch his videos but he did a great video on extracting
DNA with the shot glass method Though he used a whole one liter beaker. So be sure to check that out if you want to see how you can extract DNA without using any fancy kits and using only stuff you have
lying around the house And that’s where I think I’ll end this video If you enjoyed be sure to subscribe and
ring the bell to see when I post new videos. While sponsors for videos are great, this channel is made possible largely because of my patrons and channel members. So if you’d like to help the research and keep the videos coming, consider supporting. That’s all for now!
And I’ll see you next week!

What Gall! The Crazy Cribs of Parasitic Wasps | Deep Look


Plenty of animals build
their homes in oak trees, but it’s another thing
entirely to get the oak tree to do all the work. To build your house for you. Say you’re an oak tree,
just sitting there minding your own business, when suddenly
this tiny wasp comes along. She says hey, why
don’t you build me a nursery for these baby
wasps I’m about to have? And then she injects her
eggs under your skin. You find yourself creating an
entirely new structure, one you would have never
built for yourself. What nerve, you
might say, what gall! And you’d be right. This thing, this parasitic
wasp house, it’s called a gall. There can be dozens of types
of galls on a single tree, each one built to order for
a specific species of wasp. They’re called
gall-inducing wasps, and each gall is weirder and
more flamboyant than the next. Sometimes the wasps
prefer a mobile home. This one is called
a jumping gall. It falls from the
tree and bounces across the ground like
a Mexican jumping bean until it finds a
safe place to hatch. As a protection
against predators, galls can taste
incredibly bitter, bitter like the bile produced
by a gallbladder. In fact, the earliest doctors
believed being bitter and angry meant an excess of
gall in the body. Anyway, back to our tree. Inside the gall, the
larvae mature and develop, and as they grow they
release chemicals that tell the tree
how to build the gall. The tree is tricked
into funneling nutrients into the gall to feed
the hungry wasp larvae. Scientists call this
a physiologic sink. For the larvae, it’s like
living inside a giant banana, an endless supply of food. But the peace and
quiet don’t last long. All that free food starts
attracting uninvited guests. That original wasp
itself becomes a host for another set of
wasps, called parasitoids. One study in the UK found
17 different wasp species living in one gall. But the oak tree? It does just fine, in most cases
unharmed by the tiny rivalries in tiny houses on its
branches and its leaves.

Homework Hotline: Millipede and  Madagascar Hissing Cockroach

Homework Hotline: Millipede and Madagascar Hissing Cockroach


(CRAIG) ALL RIGHT AND NOW WOULD LIKE TO WELCOME TIM FROM THE ROCHESTER MUSEUM AND SCIENCE CENTER TO THE
SHOW HEY TIM. (TIM) HI GUYS. (DONNA) HI TIM. (TIM) GOOD TO SEE YOU AGAIN.(DONNA) BEFORE YOU TOUCH THOSE THINGS. (TIM) YEAH I WASHED MY HANDS. (CRAIG) SO YOU GOT HISSING COCKROACHES. WHERE ARE THOSE THINGS FOUND? BESIDES ON THAT LOG. (TIM) MADAGASCAR. (CRAIG) ALRIGHT. (TIM) THAT’S WHY THEY’RE CALLED MADAGASCAR HISSING COCKROACHES AND THAT IS ON
THE EASTERN OFF THE EASTERN COAST OF AFRICA. SO THEY’RE PRETTY
NEAT AND THEY’RE. (DONNA) OH I HEARD THAT. (CRAIG) YUPP YOU CAN HEAR IT. (DONNA) THAT’S WEIRD. (TIM) HISSING. THEY ACTUALLY HISS BY PUSHING AIR THROUGH THE SEGMENTS IN THEIR ABDOMEN. WHERE THEY
BREATH THROUGH. SO THEY’RE THE ONLY INSECTS THAT REALLY
DO THAT. YOU GET OTHER INSECTS THAT MAKE NOISE USUALLY THROUGH
SOMETHING LIKE STRANGULATION OR RUBBING BODY PARTS GATHER. HE DOES IT AND HE’S GOT THREE DIFFERENT ONES. THAT ONE WAS
BECAUSE HE WAS STARTLED. THEN HE’S GOT ONE FOR MATING. TRYING TO ENTICE THE FEMALES AND THEN ONE FOR FIGHTING. WHEN HE’S GOING UP AGAINST ANOTHER MALE FOR
DOMINANCE. (DONNA) NOW HE’S PRETTY BIG. HOW LARGE WILL THEY GROW AND
HOW LONG IS A TYPICAL LIFESPAN? (TIM) ACTUALLY HE’S SMALL COMPARED TO THE FEMALE. IF WE TAKE A LOOK AT
THE FEMALE HE’S ABOUT, HE’S JUST UNDER THREE INCHES. THE FEMALE
WILL GROW TO ABOUT THREE INCHES LONG. THE MALE BE TWO TO THREE
INCHES AND YOU CAN TELL THE DIFFERENCE BECAUSE THE FEMALE THE CROWN DOESN’T HAVE ANY HORNS
AND THE MALE DOES. (DONNA) OKAY YEAH I SEE THAT. (CRAIG) SO WHAT DOES THEIR DIET
CONSIST OF? WHAT ARE THESE GUYS GONNA EAT? (TIM) THESE GUYS EAT JUST ABOUT
ANYTHING. THEY LIKE THINGS, THESE GUYS EAT DOG FOOD. FOR THE PROTEIN BUT THEY CAN
LIVE ON VEGETATION JUST LIKE ANY OTHER INSECT ROACH THAT GOES AROUND. THEY’LL CHEW ON ANYTHING THAT’S ON THE GROUND. SOMETIMES
EVERY NOW AND AGAIN A LITTLE CEREAL OAT CEREAL THEY’RE LIKE YOU
KNOW JUST CHANGE PACE. SO THEY ENJOY THAT AND THEY DO PRETTY WELL WITH IT. (DONNA) ALL RIGHT NOW YOU TALKED ABOUT THE HORNS BUT ARE THESE THINGS
STICKING OUT ANTENNAS? (TIM) THOSE ARE ANTENNAS. THOSE ARE THE ANTENNAS AND THE FEMALES HAVE A LITTLE BIT LONGER THAN
THE MALE. THIS ONE HE’S LOST. HE MIGHT A LOST ONE IN THE FIGHT. AND BECAUSE HE WAS IN WITH OTHER
ONES AND SO HE TURNED AROUND WHEN I WAS ACTUALLY PICKING A
ROACH I WAS PICKING THEM UP TO SEE WHO WOULD HISS AND HE HISSED THE MOST SO I’M FIGURING HE PROBABLY THE DOMINANT ONE. (CRAIG) RIGHT. (TIM) MAYBE HAD A
LITTLE FIGHT GOING ON. (CRAIG) RIGHT SO YOU’VE TALKED ABOUT THESE
GUYS MAKING NOISES. WHAT OTHER KINDS OF INSECTS ARE GOING TO
MAKE SOME NOISES AS WELL? (TIM) WELL YOU GET YOU GET CRICKETS THAT’LL MAKE NOISES. (CRAIG) AND THAT’S RUBBING THEIR HIND LEGS TOGETHER. (TIM) THE CICADAS THEY MAKE NOISES. SO THEY
THERE’S A LOT OF DIFFERENT ONES BUT ONLY THESE HISSING
COCKROACHES ARE SOME TWENTY SPECIES OF HISSING COCKROACHES
ON MADAGASCAR. SO THEY ACTUALLY
MAKE THAT SAME NOISE. (TIM) NOW YOU ALSO BROUGHT
ANOTHER. (TIM) I DID. (DONNA) IS IT AN INSECT OR SOMETHING FOR US TO SEE. (TIM) HE’S A POD. HOLD ON. (DONNA) HE’S A POD. HE’S A TOUGHY TO GET A HOLD OF. (DONNA) NOW THESE GUYS WON’T GET OUT WITHOUT THE LID ON WILL THEY? (TIM) NO. THEY WONT GO FAR. LET ME SEE IF I CAN FIND HIM. HOLD ON. THERE WE GO. (CRAIG) HE’S GOT A NECKLACE. (DONNA) AWW HE’S GOT A NECKLACE ON. (TIM) WELL IT’S MARDI GRAS. (CRAIG) AH MARDI GRAS. (DONNA) WHAT CREATURE IS THIS AND WHERE CAN WE FIND IT. (TIM) THIS IS OUR MILLIPEDE. OOPS GOT IT ON THE BACK END. THAT’S ALRIGHT. BUT THAT’S ALRIGHT. I WON’T TELL YOU HOW IT GOT THE BEADS BUT THE KICK LINE IN THE CONGA WAS TO DIE FOR. BUT THIS IS THAT OTHER INSECT. IT’S WELL NOT AN INSECT. IT’S A POD. IT’S GOT.. IT’S A MILLIPEDE IT DOESN’T HAVE
A THOUSAND LEGS. IT’S ONLY GOT ABOUT FOUR HUNDRED. AND BUT HE’S REALLY PRETTY COOL
THEY’RE THEY’RE ACTUALLY ONE OF THE FIRST TO COME OUT OF THE
OCEAN. DURING ABOUT FOUR
HUNDRED AND FIFTY MILLION YEARS AGO SO FIRST TO TAKE THE LAND
WHERE THE MILLIPEDES AND CENTIPEDES. (CRAIG) WHAT CHARACTERIZES THIS AS A POD COMPARED TO AN INSECT? (TIM) THE NUMBER OF LEGS. (CRAIG) SO INSECTS HAVE SIX. (TIM) SIX AND THE NUMBER OF BODY PARTS BECAUSE HE’S GOT SEVERAL SENTIMENTS AND IF YOU NOTICE IF
WE CAN GET A GOOD LOOK AT HIM OR HOLD HIM YOU CAN SEE THE THE LEGS MOVE. (DONNA) HOW THEY MOVE YEAH. (TIM) THE FIRST FEW SEGMENTS WILL HAVE ONLY TWO LEGS ON EACH SECTION
AND THEN FROM FIVE BACK THEY’LL HAVE FOUR LEGS ON EACH SECTION.
(CRAIG) INTERESTING (TIM) AND GO AHEAD. (DONNA) HOW
LARGE IS HE GOING TO GET? (TIM) THIS ABOUT AS BIG AS HE’LL GET. SIX
MAYBE SEVEN INCHES. HE’S NORTH AMERICAN SO HE’S
YOUR FIND, CRAIG YOU SAID YOU FOUND SOME. (CRAIG) OH WE WERE IN LETCHWORTH WITH THE BOY SCOUTS AND THE GUY HAD ONE A LITTLE BIT SHORTER THAN
THAT BUT IT WAS ABOUT AS BIG AROUND AS THAT ONE. (TIM) WELL SAME KIND OF LOOK TO IT SO YOU FIND THEM ALL OVER BUT MOSTLY THEY’RE
TROPICAL THEY BECAUSE WELL AS MOST INSECTS OR MOST
PODS LIKE THIS THEY’LL LIVE BETTER IN TROPICS, WARM WEATHER. SAME WAY WITH THE ROACHES. THE
ROACHES WILL DIE IN COLD WEATHER BECAUSE IT WON’T BE ABLE
TO BREATH. (CRAIG) OKAY. (DONNA) NOW DOES THE MILLIPEDE HAVE ANY DEFENSE MECHANISMS? YOU TALKED ABOUT THE HISSING FOR THE
COCKROACHES. (TIM) AS A MATTER OF FACT IT DOES. IF YOU COULD SEE ON THE ENDS OF
MY FINGERS YOU’LL SEE THE
LITTLE YELLOW AND HAVE THEY SECRETE FROM THEIR SEGMENTS. AND
IT’S USUALLY SOME KIND OF A TOXIN FOR HUMANS IT’S NOT
ANYTHING MORE THAN IT DISCOLORS THE SKIN. (CRAIG) WE KNOW FIRST AID
SO. (TIM) BUT YEAH SO I’M I’M GOOD TO GO I’M SURE. BUT FOR OTHER
INSECTS IT’S A TASTE SOME OF THEM HAVE SOME MILLIPEDES HAVE REALLY TOUGH TOXIN SO AS SO AS THEY A TASTE IT ITS A NEURO TOXIN. THEY’LL STOP BITING IT AND THEN BUT IT ALSO THESE GUYS
ROLL UP INTO A BALL TO TRY TO PROTECT THEIR LEGS AS THEY GO
ALONG AS WELL. (DONNA) WELL TIM I WOULD
SHAKE YOUR HAND BUT YOU HAVE THAT THING. (CRAIG) I WILL THANKS TIM. (DONNA) IF YOU WOULD LIKE TO LEARN MORE
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