Relics Travels in Nature’s Time Machine


Piotr is a Polish born
entomologist, photographer, and author, currently
a research associate with the Museum of Comparative
Zoology here at Harvard. He focuses his research
on the evolution of katydids and related insects,
and the theory and practice of nature conservation. He received his
Master’s in Zoology from the to Mickiewicz
University in Poland, and a PhD in Entomology from
the University of Connecticut in Storrs. From 2002 to 2009, Piotr served
as Director of the Invertebrate Diversity Initiative at
Conservation International in Washington, DC. In addition to being a tap
scientist and conservationist, you will see in his
book that he’s also a very talented photographer. I bet we’ll see some
of that on the screen. He’s one of the founding
members of the International League of Conservation
Photographers, and his photography
has been exhibited at the American Museum
of Natural History, New York City, the Natural
History Museum in London, the Aquamarine
Fukushima in Japan, and here at the Harvard
Museum of Natural History. Please welcome Piotr
Naskrecki to the podium. [APPLAUSE] Thank you, David, for
this introduction. Good evening, everybody, and
thank you very much for coming. What I will be
talking about tonight is the topic of
relics that comes from a fascination–
a fascination and an obsession that I’m
sure I share with many of you in the audience– and that’s
an obsession with time travel. Ever since I was a
little kid, I dreamt of being able to go back
in time, and see the world, and organisms and
ecosystems that existed is long before a human appeared
on the surface of our planet. And I believe that
this fascination had its origin in one small,
seemingly insignificant event. I grew up in
Poland, and one time when I was coming
back from school– I was maybe eight or
nine– I noticed them on the curb side a
big rock– a boulder– with a little, beautiful
shell embedded in it. It was just absolutely perfect. It looked like sort
of like a scallop. And I knew I had to have it. So I sneaked out at
night, and I dug it out, and I left a big, gaping
hole in the sidewalk, that I’m sure made a
lot of people unhappy. And I lugged it home. And I showed it
to my grandmother, and asked her what
she thought about it. And she hesitated for
only about a second. And then she proclaimed
that, well, that’s a remnant off the
Great Flood and this is one of the animals that
didn’t make it to the Ark. And a good, little
Catholic boy that I was, I, of course, accepted
her explanation. But at the same time, it
struck me as counterintuitive that this aquatic animal
would drown in a flood. So I went to my father. My father was an astronomer,
a man of science, to get some extra explanation. And together we determined
that that shell probably belonged to a brachiopod, an
animal superficially similar to mollusks. And based on the
appearance of the shell, it might have been
from the period called the Cretaceous, and about
60 million years or so. And that really blew my mind. I started reading,
or rather browsing, books on paleontology,
most of the information went away– above my
young, little head. But it opened up to me
this wonderful world off these past life
forms and ecosystems. But the one thing I
couldn’t wrap my mind around is the fact that I will
never, ever see them. And then I stumbled upon
something very interesting, a little bit of news that I
found absolutely enthralling. And that was a piece of news
about the discovery of a fish off the coast of
southern Africa, the fish called the
coelacanth, or Latimeria. And there was a fish that
had been considered extinct for at least the last
60 million years. And here it was– living,
breathing fossil animal. So ever since, I’ve been
fascinated with the notion that there might be places and
organisms that somehow preserve in their appearance, or
biology, or physiology, or genes, fragments of
these ancient worlds. And this is what
this book is about. This is not a book
about living fossils. There is no such thing. But it is about lineages and
ecosystems that date way back, and for one reason
or another, have been able to preserve
these ancient elements in their appearance,
biology, or behavior. And so what I would
like to do is, I would like to take you now on
a little trip around the globe. And we’ll visit a few of those
lineages, and a few of those places that I find
particularly interesting. And we begin our journey on
the islands off New Zealand. New Zealand is special. New Zealand has been isolated
for the last 80 million years, since the time it got
separated from the rest of this giant
supercontinent, Gondwana. And because of its
isolation, it managed to preserve in its biota
these little snippets of these ancient worlds. And none is more emblematic
of it than, of course, the tuatara. Tuatara is a reptile
like no others. It’s the last remaining
member of the order called Sphenodontia,
an order of reptiles that was quite rich in
species and widely distributed in the Jurassic and Cretaceous. There were lots of
Sphenodontia species, both aquatic and
terrestrial, but tuatara is the only one remaining. They are closely related
to lizard and snake, or so-called squamates. But they’re not the same animal. They share the same
ancestor, but they divert very, very early on. And we know the
tuatara is unique because it preserves in its
body these telltale signs of its ancient provenance. When the tuataras
were first discovered, the first exemplar, this
first skull of the tuatara was sent from New Zealand
to London in 1830. And the person who
received the skull didn’t quite
realize what he had. And he described it as another
species of an agamid lizard. But when you look at
this skull, you’ll notice that it has
elements that are not present in any
other reptile today. It has so-called fully
developed temporal fenestrae, these windows behind the eye. All other reptiles, all
lizards, and all snakes have lost this, what’s called
the jugular bridge here. And they have a very,
very different skull. This skull, and
some other elements of the skeleton of
the tuatara tells us that this is a very,
very ancient animal, at least coming from a
very, very ancient lineage. So how did they manage
to survive for so long? Now, the tuatara is
not the only reptile that you’ll find New Zealand. There’s a number of lizards. There’s actually
quite a bit of it a species radiation, both
among skinks and geckos. And yet, tuatara
was able to compete with those modern reptiles. Well, there are several reasons
for that– several very likely reasons. One of them is the tuatara
loves coled weather. It has the lowest
optimal temperature of any reptile living today. And it actually can feed,
mate, and essentially live very fulfilling life when
the temperature drops to a very low 60s
or even the 50s. And no other
reptiles living today can function– fully function–
in those temperatures. This is most likely a
very recent adaptation, but one that allowed the tuatara
to out-compete other reptiles on the islands. The second reason why
the tuatara has probably been able to survive is that,
for some strange reason, New Zealand never had
native terrestrial mammals. The only mammals,
native mammals, that you’ll find on New
Zealand is a small handful of bats and these fur seals. And this one is very
clearly telling me that it’s going
to bite my leg off if I don’t move
away a little bit. I was really getting too
close to this animal. But anyway, so there
was no competition from terrestrial
mammals on New Zealand. And that was probably why
tuataras were able to survive. Now, that has, of course,
changed within the last, let’s say 2,000 years. 2,000 years ago, the first
humans arrived on New Zealand. These were Polynesian
people, who later became the Maoris, the
native culture of New Zealand. And they brought with them, as
expected, domestic animals– pigs, dogs– and they
also– inadvertently, of course– they
also brought rats. Now New Zealand suffered the
second wave of colonization in the second half of the 19th
century, when the British came. And they decided to turn this
unique pearl of biodiversity into a South Pacific
version of England. And they brought with them
pretty much everything that they could, including most
mammals, most European mammals, for either their
hunting pleasure or for some other
bizarre reasons. And they also brought
with them 25,000 species of non-native plants. And what that
caused– first of all, the mammals that they brought
caused an absolute devastation within the native fauna
of birds, and reptiles, and amphibians, and
insects, and so on. 42% of native birds on
New Zealand are extinct. The non-native, invasive, fully
established vascular plants outnumber, in terms of species
and biomass, the native flora. So New Zealand is a catastrophe
of unimaginable proportions. And not surprisingly,
things that used to be native to the
islands, such as tuatara, are now mostly extinct. There are no free-living
tuataras on New Zealand. The only place where you
can find native populations of tuataras on tiny,
little outlying islands in the Cook Strait
that separates the North and the South Islands,
and in the Bay of Plenty. And this is the only reason why
this has been able to survive, because rats were not able
to get to those islands. And that saved that species. So now conservationists
in New Zealand are really, really trying hard
to rebuild this population. There’s a captive
breeding program for the species at the Victorian
University in Wellington. And they have also established
a small reserve on the mainland, on North Island near
Wellington, where a wild or semi wild
population of tuataras is actually successfully
breeding right now. So two years ago, the first
so-called wild tuataras hatched on the mainland
of New Zealand– probably the first time in
at least 200 or 300 years. But when tuataras were–
or tuatara relatives, sphenodontidae– were still
common across the globe, they probably lived
in an environment that was populated by a plant,
an ancient, ancient lineage of plants that we
can still witness in many places of the world. But we can really see a habitat,
a truly Jurassic habitat in one place– in South Africa. And the plants I’m
talking about, of course, are the cycads. Many of you, I’m sure, are
familiar with the cycads. Cycads are frequently lumped
together with palm trees. But a palm tree to a
cycad is about as close as a cow is to
Tyrannosaurus rex. These are ancient,
ancient plants. Their roots are firmly
planted in the Permian. The lineage is at least
250 million years old. And yet they have been able
to survive quite successfully. And actually, just about out set
six or seven million years ago, cycads underwent another quite
spectacular species radiation. So all the species that we
see now are relatively young. But the lineage itself,
and most of the morphology and physiology of the
cycads as we still witness, date way, way back. So how did this lineage
manage to survive? Again, there are many
different reasons. So this is, by
the way, a glimpse of the cycad forest– the
last remaining cycad forest in the world, which
is in a place called Modjadji in the Limpopo
Province of South Africa. And if you’ve ever
been to South Africa, you’ve probably
never heard of it. But if you ever go there,
try and make a trip to the Modjadji Forest. Walking among these
cycads, it’s really like a trip back in time. It’s absolutely,
absolutely spectacular. These are enormous,
enormous, trees. They’re at least 30 feet high. And each of these
trees is probably close to 1,000 years old. It’s an absolutely
incredible place. So how did they
manage to do that? How did they survive? Well, the reasons are,
again, two or three-fold. First of all, the one
thing to know about cycads, if you were to take away
one bit of information, they are all deadly. They are extremely,
extremely toxic. The tissues of all cycads
are saturated with toxins. These are not just
regular toxins. These so-called genotoxins. These are toxins
that will actually alter your DNA, which
means that if you ingest those toxins, if you don’t
drop dead immediately, they will start spawning
all kinds of mutations. So eventually, you
will die of cancer. Not only that, they
will also alter DNA in your reproductive
cells, so your children will develop cancer
from the cycads. So it’s not surprising
that cycads really do not have natural predators. There are no a big
herbivores that eat cycads. There’s a very small
handful of insects that can actually
eat the cycad tissue, but it’s really
very, very small. The only exception in terms of
eating cycads are their cones. And some cones, they are. Cycads produce the largest
cones in the plant world. A single cone can
be three feet long, and weigh about 80 pounds. And they look like this. They are spectacular. They’re absolutely spectacular. And if you see something that
has this color in the plant world, that’s usually some
kind of advertisement. And of course, this cone is
telling birds and monkeys that it’s OK to eat me. So this part– this
is the only part of the cycad that’s
not absolutely saturated with toxins. And that’s why birds,
such as hornbills you often see in South
Africa, hornbills feeding on cycad cones. And they can easily digest this
soft, brightly colored tissue. But of course, the seed
that’s contained in it is very, very toxic. So it passes undigested
through the digestive tract of the bird, and
then it sprouts. So toxicity is probably
one of the main reasons why cycads have
been so successful. The other reason is that
cycads are very good at forming meaningful relationships. And one of the relationships
that they formed was with a group of
small organisms known as cyanobacteria. Cyanobacteria, also known
as blue-green algae, are one of few, if
not the only organism in the world that is
capable of sequestering, or getting its nitrogen directly
from the atmospheric air. We all need nitrogen to live. Animals such as humans get their
nitrogen from the food we eat. Plants get it in some kind of
a soluble format from the soil, from all kinds of salts
that contain nitrogen. But cyanobacteria can get
it directly from the air. And cycads have created
a symbiotic relationship with cyanobacteria. They have, actually,
special roots– they’re called coralloid roots–
that contain cyanobacteria. And those cyanobacteria
provide nitrogen to the cycad. What it means is that cycads
can grow absolutely anywhere. They can grow on
virtually sterile rocks, like these karsts here. Karsts are rocks that
contain almost no nutrients. There’s no soil there. And yet, cycads can attach
themselves to these rocks and survive quite
well, because they get their oxygen and
carbon from the air, and their nitrogen from their
cyanobacterial symbionts. So that’s probably
why they’ve survived. So South Africa, but cycads are
not the only botanical wonders, ancient botanical wonders, that
you’ll see in South Africa. The western part of South
Africa, almost the entire west coast, is a place of
incredible botanical richness. This place is so
rich in species, unique species of
plants, that it has been designated as a floral kingdom. The entire world is divided
in only six such kingdoms. For example, most of North
America, Europe, northern Asia, and Africa north of
the Sahara, all put together create another flora
kingdom called Holarctic. And the Cape Floral
Kingdom is only the size of the State of Maine. And it contains an equivalent
number of unique families and species of plants. There are about
9,000 unique species of plants in South Africa. And the reason why we have
it– to understand that, we have to go a little
bit back in time. About 10 million years
ago, southern Africa and South Africa were very
tropical the entire continent was covered with, essentially,
a rainforest or very tropical types of vegetation. But then in the Miocene, about
six or seven million years ago the ice of the
Antarctica started melting. And that resulted in the
creation of a very, very cold oceanic current
called Benguela that still flows around the
western coast of Africa. What it did to the
climate of Africa– the climate became, in parts,
much dryer, but also much, much colder and far more seasonal. And those tropical plants
that used to grow there couldn’t cope with it. And they were very
quickly replaced with this type of
vegetation– vegetation that’s essentially heath. So all these plants that
you find in South Africa are mostly heathers and
relatives of heathers. And their diversity is
absolutely through the roof. Just to give an example,
there are six species of heathers in North America,
species of the genus Erica– six species. In South Africa, there are 658. And not only there are these
huge numbers of species, there’s also an enormous
what’s called floristic species turnover. You can take three
steps, and you will find a very, very
different botanical community. So not surprisingly, if you
have such incredible species richness in the
plant communities, that will be reflected in
the insect communities. And this is what I work on. I work on insects
that sing– katydids, crickets, grasshoppers. And what I discovered
with my colleagues is that these dense bushes
of heathers in South Africa are home to an incredible
diversity of grasshoppers and katydids, most of which are
still undescribed and unnamed by science. So we found that almost every
species of these heathers will have its own
little grasshopper. And some of them are
incredibly cryptic, very well adapted to living
in this dense vegetation. Most of them are,
surprisingly, wingless. And that’s also
one of the reasons why they have remained
undescribed for so long. When other entomologists
saw something like that, they assumed it was a nymph
or larva of something else, and just kind of dismissed it. But it turns out that there’s
this incredible radiation of these tiny, wingless
insects associated with these thick heather bushes. And again, it makes
sense biologically. I mean, if you live in a very
small patch of vegetation, very dense, surrounded
by similar patches, there’s really no need to fly. Because you are surrounded
by your own kind. But these tiny,
cryptic-looking grasshoppers are not the only kind that
you’ll find in South Africa. You will also see the
opposite end of the spectrum. You’ll find gigantic,
brightly colored species. And that’s, again, related
to the botanical diversity of this region. Many species that grow in this
South African vegetation, which by the way, is
called fynbos, fynbos meaning fine or small
bush in Afrikaans. Many of these species
are highly toxic. Those plants contain
secondary compounds. And some of these
grasshoppers were able to sequester those
compounds– sort of it eat them and adopt them
for their own defense. And they advertise this
fact with, first of all, with their size and their
very bright coloration. So beautiful and colorful
are these insects that, unfortunately,
kids in Africa will sometimes eat
them, and promptly die. Because one of
the main compounds that these grasshopper
carry are what’s called cardiac glycosides. These are alkaloids that will
actually stop your heart. But what it also tells me,
that we humans have somehow lost the ability to read
the language of Nature. No sane animal would eat
anything that looks like this. This is a warning color. If you see bright yellow
and black, that tells you, don’t eat me. And yet we somehow managed
to forget that language. Now let’s take for a second
in Africa, in South Africa, but let’s move a little
bit farther north, where the vegetation changes
into an ecosystem known as succulent karoo– again,
very, very high endemism, but far less water. You still get seasonal
rains with some regularity, but there’s much,
much less of it. So plants adapted to
this type of environment by developing these
kind of storage systems. Their leaves or their stems turn
into these cisterns of water that allow them to survive these
prolonged periods of drought. Succulent karoo is also
a very rocky terrain. This is what succulent
karoo looks like just after the spring rains, because
the rains come every year quite regularly, usually in September,
which is the southern spring. But they only last for
about a day or two, and it’s very little of it. And then everything suddenly
explodes and starts blooming. And, of course, a lot
of interesting animals start coming out. But the one thing I
want to point out here is, notice how many
rocks there are. This is very, very typical
of the succulent karoo biome of South Africa. You have all these
incredible rocks. And of course, you
have the animals associated with those rocks. And if you live among rocks,
you have two possible strategies of avoiding being
detected by predators. One is to look like a rock. And there is a whole
lineage of insect– this is a lineage of
enormous grasshoppers. These are grasshoppers
almost the size of your fist that really look like rocks. They spend the entire
day motionlessly. And they only become active
at the very end of the day, when they start kind of moving
slowly, and chewing vegetation. The second strategy, if
you live along rocks, is to sort of live like
there’s no tomorrow. And if something sees
you, you make a mad dash to the nearest crevice. And you wedge yourself in,
and then you inflate your body and stay there. This is a member of an African
family of lizards called [INAUDIBLE]. And they employ this strategy. They will wedge themselves
between two rocks, puff up with air, and they’re
absolutely impossible to pull out by a predator. Now this ability to kind of
puff up and become bigger than you really are seems
to be a very common strategy among these southern
African animals. This little piglet is a frog. It’s shovel-snouted frog
called Hemisus marmoratus. And normally, it looks
just like any other frog. It’s kind of flat and not
particularly conspicuous looking. But if it feels
threatened in any way, it immediately
starts gulping air, and turns into
something like that. Which, as you can imagine,
is not the easiest thing to swallow if you’re a snake
or some other small predator. Other animals employ similar
strategies, even chameleons. You know chameleons
as these animals whose main line of defense is
to blend in with the background, and become inconspicuous. You know that they
can change skin color because of the chromatophores
they have in their skin. But sometimes they
have to cross the road, or do something that
makes them feel exposed. And this is what
they will often do. Again, they will puff up,
start gaping their mouth, and look very, very scary. Of course, they’re
completely harmless. And then there’s
another group of kind of chunky looking animals that,
to me, is the most fascinating African animal. And I’m talking about
bladder grasshoppers. These are absolutely
fascinating animals. These are big, big
grasshoppers– again, this big. And this is actually
one of the oldest lineages of grasshoppers. They probably go
back to the Triassic. These are some of the
earliest grasshoppers that we know from the fossil record. And this enormous body
of this grasshopper is filled with air permanently. So they cannot deflate. They are always kind
of puffed up like this. And why do they do that? Well, as you can imagine,
as you probably know, grasshoppers can sing. So they use this
incredible inflated abdomen as a resonator to
amplify their song. And they produce this song– I
don’t know if you can see it– but it’s like a little
ridge here of little teeth. And so they rub their hind
legs against those teeth. And the sound that they
are capable of producing using the combination of
this balloon and these ridges can be heard from a
mile and a half away. You can scream as
loud as you want, and you probably will not be
heard from a mile and half away. But these insects, these
individual insects, can be heard from
such a distance. It’s an unbelievably loud sound. It has to be heard to believe. Unfortunately, I don’t
have a recording. I should have
brought a recording. But anyway, absolutely
fascinating group of organisms that also
have incredible biology. But interestingly
enough, because this is such an ancient,
ancient lineage– this is one of the
first grasshoppers that ever appeared– they don’t
even have fully developed ears. And perhaps that’s why
they have to be so loud. They don’t have tympanal organs. They perceive sound with
single individual neurons that attach– there’s a pair
of neurons attached to each of abdominal segment. So they actually have twelve
neurons all along their body. Each of these
neurons is sensitive to the sound vibration. That’s how they perceive sound. But they don’t have
ears to speak of, like other grasshoppers and
katydids, which have very, very sophisticated hearing organs. OK, well, let’s move on. Let’s stay on the
African continent, because I would like to show
you a very different place. Rather than focusing
on one organism now, I want to show you an
entire ecosystem that is sort of a relic of the past. And we are now in the country of
Ghana, which is in West Africa. West Africa, again, about
10 million years ago, was completely covered with
forests– lowland and middle elevation rainforest. And now we have very
little of it left. There’s a little bit
of it in Liberia, a little bit in Cote
D’Ivoire, and also in the country of Ghana. There’s a small patch of what’s
called the Upper Ghanaian Forest left in a place
called the Atewa Forest. It’s a very, very special place. Atewa Forest is a small
fragment of forest located on top of a plateau. This plateau is only
about eight miles long, maybe three miles wide, and
it’s about 2,500 feet high. But on top of the plateau,
we have a fragment of forest that we know, through a very
good paleontological record, it has literally has not changed
in the last 10 million years. It has always been there. And by virtue of
always being there, it has acted as a sanctuary
of forest biodiversity, even when the forests around it
have disappeared or reappeared. And so following extended
periods of drought, this Atewa Forest
was able to sort of reseed this biodiversity
so the forest could regrow in other areas in West Africa. So it’s a very, very
important forest. It’s a sanctuary of
sylvan biodiversity. And the reason I
know about this place is because I have done some
work there with my friends who were conservation biologists. We have done some survey
work and conservation work. And when we first
went there, we were absolutely astounded by
how humid this place is. You don’t expect
this type of humidity in West Africa, which
is generally fairly dry. But this place has
a humidity that’s very similar to what you’ll
find in lowland rainforest in South America
or Central America. And that’s why you have a
very rich flora of epiphytes. Everything is just loaded
with orchids, and lichens, and mosses, and so on. And of course, this type of
habitat is of course home to an incredible
diversity of animal life. This is what the interior
of the forest looks like. It’s a very, very dense forest. You also, of course, have
these enormous emergent trees with tree trunks
the size of a bus. But a lot of it is
very, very dense, completely permeated with
this network of lianas. And what we found there
was a diversity of animals in almost any group
that completely exceeded our expectations. We found there the
highest diversity of butterflies anywhere
on the African continent. This is just a sampling
of some caterpillars that we collected there, none of
which we were able to identify to species yet. They may not be new to
science, but this just shows you how little
we know about biology and developmental biology
of a lot of these insects. We found incredible
diversity of ants. I want to point out
this one particular ant, not because it’s
particularly rare or new. This is not a new species. This is a known species
of a genus Chromatogaster that also occurs
in Massachusetts. But there’s something
very interesting about the behavior of this art. What you can see here, they’re
sitting on these red balls, which are actually insects. These are what’s
called scale insects. They’re relatives of
aphids and cicadas. And these insects are
completely sedentary. And they feed on plant juices. Plant juices, of course,
are rich in water and sugar, but not much else. So they excrete
the excess of sugar in the form of what’s
called honeydew. And you can see here
this little droplet this ant is drinking in here. So the ants collect the
honeydew of the scale insects, and provide protection from
predation– common behavior. You’ll see it in
your own garden. If you go out in the summer,
find a bunch of aphids, watch them for a
while, sooner or later, ants will come and
display this behavior. What’s more interesting
is that later I found out that these
ants were leaf-cutters. Now leaf-cutting behavior,
up to this point, has only been known
from the New World, from South and Central America. And here they are, in
Africa– ants cutting leaves. These are ants that
are not related to the leaf-cutter
ants of South America, but they exhibit a very,
very similar behavior. Now, we don’t know what they do
with this fresh plant tissue. In the neotropics, ants
use the plant tissue to grow fungi on
which they feed. Here, it’s possible that
the ants use it merely to build their nests. We don’t know yet. But it is the first case
of leaf-cutting behavior in the Old World. And it also shows
you how little we know about the behavior of most
invertebrates in the tropics. Now the group that I work
on, primarily, are katydids. And I found in the
Atewa Forest, again, the highest diversity of
katydids anywhere in Africa. I found katydid diversity
comparable to the one you will find in
the Amazon, which is unheard of for the
African continent, including this animal. This is a bark katydid. I don’t know if you
can even see it. This is the eyes. This is kind of a face on shot. This is an animal that
lives on tree trunks, and blends absolutely perfectly. And a lot of these katydids
in these African forests are absolutely perfect
mimics of plants. This is one strategy. This is another strategy. This is a type of behavior you
will not see in the New World. These katydids will flatten
their body against the leaf, and they will sit
upside down on the leaf so that the light during the
day shines through their bodies. And they almost
completely disappear. What we also found in Atewa
is very high diversity of amphibians. In fact, we found there,
in this small area– again, eight miles
long– we found about 50 species of frogs,
some of which we know are extinct everywhere else. So we found some critically
endangered species known only from this one last population. Even though we didn’t sample
this particular group, we did find the world’s
largest scorpions there. This is what’s called
the emperor scorpion, Pandinus imperator. Again, this is a species
whose range is shrinking, and it’s becoming
rarer and rarer, but we found a very
healthy population. The reason I’m
showing it to you is because I want to show you a
certain thing about scorpions. As you probably
know, scorpions, when exposed to ultraviolet light,
will start glowing blue. It’s a very
interesting behavior, and we still don’t know
exactly why they do it. The prevailing theory is that
this coating with the substance that’s called fluorescent
beta-Carboline helps scorpions reflect
ultraviolet light, and thus reduce the amount of
ultraviolet radiation getting to their tissues,
which is a good thing. There’s also a recent
study that seemed to indicate that this
ultraviolet reflecting coating helps the scorpions to decide
whether it’s day or night. But I don’t quite buy it. But anyway, the
point is that they are coated with this
UV-reflecting substance. And we will see again
in a little while in a very different animal. In terms of
mammalian population, we found an incredible
diversity of mammals, including six
species of primates, including chimpanzees. We found incredible
diversity of bats, including some new
species of bats, and some species of shrews. We also found there the
largest snails, land snails, in the world, genus Achatina
has several species in Atewa. But unfortunately, they are
getting rarer and rarer. And the reason is, that
they are very tasty. So people treat
this Atewa forest as a sort of like a kind
of a walking kitchen. And not only do they harvest
those increasingly rare snails, illegal bushmeat hunting
is really rampant. And that has already
severely affected a number of populations of
large birds and mammals. For example, we know
that giant parrots used to be very common there. Now they are extinct in Atewa. Several species of
antelopes, forest antelopes, are now extinct in Atewa. That’s exacerbated
by illegal logging. And illegal logging kind of
comes in waves into Atewa. And at certain point, in
2002, the Ghanaian government actually had to send
the army to Atewa to stop illegal
loggers from actually taking the whole forest apart. But by far the largest
threat to Atewa is mining. So as I mentioned, Atewa is
situated on top of a plateau. The problem with that
is that plateau is made entirely out of bauxite. So mining corporations,
mining companies, have been drooling
over the rights to mine these deposits for years. And we were able to,
our conservation group, have been able to convince the
local authorities to withdraw their permission to
mine these resources. I mean, this is a really,
really small part of, a small chunk of the forest. And even a small-scale
mining operation would have completely
destroyed it. But unfortunately, now
a new mining company, a Chinese mining company is,
again, trying to get into Atewa and essentially strip
this inconvenient greenery off the top and get
to the bauxite ore. So my colleagues
and I were trying to turn this forest, which
has now the designation of the Forest Reserve,
into a proper National Park and give it the
permanent protection. And so we’ve been trying
to– we are constantly talking to the government of
Ghana and local governments, and trying to
convince them that we will be able to give them,
or help them, develop alternative sources of income,
such as ecotourism and so on. But it’s very
difficult. We’ve been trying all kinds of
PR stunts, like naming new discovered species
after this place, and making a big deal out of it. So this is, by the way, the
world’s largest dinospider, or Ricinoides. This is, again, a very,
very ancient lineage of organisms that goes
back to the Carboniferous and hardly changed. And we found the largest
species in Atewa. It’s 11 millimeters long. But it is a fascinating animal. And we’re using these
types of discoveries to kind of strengthen the
message of the uniqueness of this place, and the
need for its protection, because this place really
needs to be protected. Because if Atewa
disappears, that means that 1,000 years from
now, there will never, ever be a chance for the forest
to regrow in West Africa. Anyway, I don’t
want you to leave with the thought
and the attitude that you have to go to all
these tropical and remote places to see these incredible
ancient lineages and places. Actually, some of the
most fascinating relics you can find right here at home. And some of my favorite
ones are in Massachusetts. I don’t know if you
know– I’m sure you know the town of Concord. But I don’t know if you are
familiar with the place called Estabrook Woods, which is
a small patch of woodland very close to Concord. And the reason I
know about this place is because a friend
of mine told me that you can bring your dogs
there, and they can run. And so we’ve been bringing our
dogs to Estabrook for years. But I never thought
much about this place as a place full of
interesting biodiversity. Estabrook Woods– it’s not old. The woods itself is
maybe 150 years old. That used to be all pastures. And as you walk in
Estabrook Woods, you see these– how many people
have been to Estabrook Woods? Oh, quite a few. So you know that
when you walk there, you see these rock walls. And these are the
old demarcation lines for pastures and meadows. And the woods themselves
are not very old. But it then it occurred to me
that if I just kind of changed my perspective, and look at
the Estabrook Woods the way my dogs see it, I may
see something else. So I followed this
little fellow named Max, who is very, very inquisitive. And he always has his
snout right to the ground. And when I started
looking at this forest from his perspective, this whole
universe kind of opened up. And the first thing I
noticed were these plants. They are called lycophytes. And lycophytes are the
oldest and the first vascular plants that appeared on
the surface of the planet. They are not the first
plants that grew on land, but they were the first one
that colonized the land, and developed a vascular system. So they are very, very old. And there are several
species of these lycophytes in Estabrook Woods. This is Dendrolycopodium. And this is– I forgot
the species right now. Diphasiastrum–
that’s another genus. And there are several others. And they’re very,
very interesting. They still have this kind of
an ancient reproductive cycle. They don’t produce flowers. They don’t produce seeds. They reproduce through spores. Another lineage
of ancient plants can be seen in Estabrook Woods. And those are the
horsetail ferns– again, very, very old lineage. If you could go there very early
in the spring, you’ll see this. You’ll have to sit there for a
long time to actually see this. But you will see those very,
very young plants that develop. They still don’t have the
chlorophyll in their tissue. But this is the reproductive
phase of the horsetail fern. And they reproduce
through these spores. These spores fall to the
ground, and then they develop, and actually a
reproductive plant that’s diploid, that produces
gametes and actually produce another green plant that
has chlorophyll and so on. By the way, the horsetail
ferns do not have leaves. So when you see a
horsetail, it has these kind of spiky
things around the stem. These are just another branches. And those black
rings that you’ll see sometimes around the stem,
these are the actual leaves. Now, the interesting think
about both of these plants, the lycophytes and
the horsetails, is that these two groups
of plants, plus the ferns, essentially made our
civilization what it is now. These plants have propelled
the Industrial Revolution– not these very plants,
but their ancestors from the Carboniferous. Because their bodies,
deposited in the ground, created these enormous
deposits of coal, which propelled the
Industrial Revolution and our technological
advancements. So it’s thanks to
those plants that we can sit here now and watch
this interesting slide show. But another interesting
organism that I found in Estabrook Woods that,
to me, is just absolutely mind blowing, is, of
course, the magnolia trees. Now, I’m told that the
magnolia trees that grow in Estabrook
Woods are not native, that this is a sort
of escaped population. But nonetheless, the
very same species of magnolia, which is
called Magnolia tripetala is native to Massachusetts. And actually,
Massachusetts forms the northernmost distribution
range for magnolias. Now the reason why
it’s interesting is because for the
longest time, botanists thought that magnolias hold
the key to our understanding of the evolution of the
pollination syndrome, and actually, the origin
of flowering plants. I don’t know how
many of you have read Charles Darwin’s writings. But one of the things
that perplexed them, until the very end
of his life, was the origin of flowering plants,
because they suddenly appeared. They first appear in
the Cretaceous deposits as just some individual plant. And 10 million years
later, they are over. And they are the dominant
plant form on Earth. So they just kind of
exploded everywhere. And he couldn’t understand
how did that happen. And now we know that this
explosion of flowering plants had to do with the
co-evolutionary process between plants and insects. And magnolias are some
of the earliest examples of the development of this
pollination relationship between plants and insects. If you look at the morphology
of the magnolia plant, it’s still very, very simple. It has a sort of a spiral
arrangement, which you’ll see in these early plants. But most importantly,
when you start looking at who
pollinates magnolias, you’ll quickly discover
that it’s beetles. And the reason it’s beetles is
because when magnolias first appeared, there were
no other pollinators. There were no butterflies, no
bees, very, very few flies. So the magnolias had to do
with what was available. And what was
available was beetles. Now, beetles are very
unsophisticated players. They’re actually called
mess and soil pollinators, because they just get into
flowers, start tumbling around, and get covered with pollen. Then they leave, go into
that another flower, chew up a hole
and damage things, but eventually, they
pollinate something. From that, other
types of pollination have developed– much,
much more sophisticated. And many other groups of insects
have developed relationships with plants. But this is one of the
very, very early chapters. And we can still
see it, almost as if it was 136 million years
ago in Estabrook Woods. Now another very
interesting thing about Estabrook Woods, if you go
there very early in the spring, you will notice– first of all,
you will hear these things. I don’t know if you can see it. There’s a frog there. That’s the wood frog. And you will hear them
calling, sometimes as early as late February. But in March, you can hear
them all over the place. And they are calling
from these small bodies of water called vernal pools. These are bodies of water that
are created by melting snow, and they accumulate in
little holes in the ground. And that place, the vernal
pools of Estabrook Woods are home to one of the oldest
surviving lineages of animals. And I’m talking
about these animals. They’re called fairy shrimp. This is a photo I took in
one of these vernal pools. And when I saw that, I was
just absolutely astonished. To me, this is as beautiful
and as a rich as a coral reef. And you find this in a body of
water that is only about a foot deep in the middle
of the forest. Now, fairy shrimp belong
to a group of crustaceans called branchiopods. And we have fossil records
of very similar branchiopods dating back to Precambrian. So they are at least
half a billion years old, and they have hardly changed. And again, you
have ask yourself, how did they manage to do that? And again, the
answer is probably related to their very
sophisticated and multifaceted survival strategy. First of all, they have
a fantastic back-up plan for surviving life in this very
unpredictable and ephemeral environment such as
the vernal pools. They develop very, very quickly. In about two weeks,
they hatch from eggs, achieve adulthood,
and reproduce. But the key is their eggs. Their eggs can survive
essentially anything. They can be frozen
into liquid nitrogen. They can be put
in boiling water, and they will still hatch. They can sit in this dormancy
for many, many, many years– dozen years or more. They can be distributed by wind. So they can colonize
almost any habitat. And at one time, I was in
Namibia, which is one of the, if not the driest
country in the world. And I was lucky enough to
witness one of the very, very rare rains in the Namib desert. And so the little
indentations in the rocks are filled with water. The next day, those indentations
were full with fairy shrimp. I had no idea that
there were eggs there. Those eggs were probably
brought in by wind from Kenya or somewhere else. And they took that opportunity,
hatched, reproduced, and then they disappeared. And a week later,
there was nothing left. But I’m sure that
that entire rock was covered with eggs
that will probably wait another 20 years to hatch. So it’s not surprising
that NASA uses fairy shrimp and their
relatives as model organisms to study survival of
life in outer space. And that’s probably
one of the reasons why they have been able
to survive for so long. I mean, these are really
fascinating organisms. This is an adult male. They are very
sexually dimorphic. This is a male holding
the female with his– he’s got a pair of big
pincers, which are actually modified antennae. And the females develop
these big egg sacs with eggs. So these animals
are fully adult, and they’re only
about two weeks old, and they will probably
die the next day. But these eggs can
survive for years. Now, the last organisms I
would like to mention to you is my absolutely most
favorite relic there is. And I’m talking, of course,
about horseshoe crabs. Horseshoe crabs have been around
since the Ordovician, about 450 million years. And they have hardly changed. In fact, if one crawled
right in front of me, one of the old ones,
crawled right in front of me on the beach of
the Delaware Bay, I probably wouldn’t even notice
anything unusual about it. They have hardly changed–
their morphology, that is. We know that their
behavior and physiology have changed quite significantly
over the last 150 million years or so. For example, we know that most
of the Jurassic and Triassic horseshoe crabs were
probably freshwater. Right now, we have four species
of surviving horseshoe crabs. Only one of them is a
semi-freshwater one. And there were even some land,
terrestrial, horseshoe crabs. One of the species also
was, most likely, arboreal. So it was a very different
type of lifestyle. But nonetheless,
their morphology has remained
essentially unchanged. Now remember that
scorpion I showed you? Now these are horseshoe crabs
exposed to ultraviolet light, and they look very much
like those scorpions. And what it tells you– one
of the things that it tells you– is that they are
actually related to scorpions. Horseshoe crabs are
not crustaceans. They’re chelicerates. They are related to
arachnids– scorpions, and spiders, and so on. But what it also tells
you is that these are animals whose
main, principal sense is that of vision. As you know, they come
out in these huge numbers in early summer, late
spring and early summer, to lay eggs on the beaches
of the east coast of North America. And that’s how they
find each other. They find each other by looking
for these glowing bodies in these murky waters
off Delaware Bay. But it’s also interesting,
because it can tell you a lot about what happened to
that particular individual. As you can see, this guy
here– somebody really wanted to eat him. I mean, somebody has been
kind of scratching at him. Adult horseshoe crabs have
almost no natural enemies. There are only two things
that can potentially eat a horseshoe crab. It’s a big shark, and a
really, really big turtle. So what I suspect
happened here is that a turtle that
wasn’t big enough was trying to eat
that horseshoe crab. Other than that,
adults really have no enemies– with
one exception, which I’ll show you in a second. So horseshoe crabs come
in these huge numbers every year to lay their eggs
on the shores of Delaware Bay. This type of behavior,
when the eggs are laid in a very, very
different environment from that where the adults live, is
called the export strategy of reproduction. So they export their eggs
to a different environment. They hatch there. And then they return to the sea. And the reasons for
that is probably because of the number of
predators, potential predators, in the sea that would
be interested in eating those eggs. And those eggs are
very, very nutritious. This is just a view of the beach
after the night of spawning. And it looks like if a
battle had taken place there, like these tracks, like
thousands of small tanks went through it. But what you’ll find
the next morning is millions and
millions and millions of these nutritious eggs. Two weeks later,
they’re all in the sand. Two weeks later, these
little larvae will hatch. They’re called trilobite larvae. They really look like
tiny, little trilobite, to which, by the way, horseshoe
crabs are quite closely related. And then they enter the
ocean and start swimming. Now, of a clutch of
about 100,000 or so eggs, maybe one will actually
reach adulthood. So it’s a very kind of low
investment in individual egg type of reproduction. So this is the main enemy,
now, of the horseshoe crabs. When they come out on shore,
they often get stranded. And they often get
stranded on their backs, when their soft parts
are fully exposed. And seagulls and raccoons and
other animals will attack them. And they will actually will
try to rip out body parts. But surprisingly, many
of these horseshoe crabs will survive these
horrific injuries. And they will survive
it because they have this fantastic line of defense. Now, notice this blue goo. That’s their blood. Their blood is copper based,
as opposed to iron based, so it’s not red, but blue. And they don’t really have
an immune system like we do, but they have an equivalent
of an immune system. They have a certain type
of cells called amebocytes that are very, very sensitive
to contamination with bacteria. And the moment amebocytes detect
any kind of a contamination, they will instantly form
this massive, massive clot that will prevent these
antigens from entering the body of the crab and
developing an infection. So people realized
that that can actually have a very, very good
application for us. So there’s now an
entire industry developed around harvesting
horseshoe crab blood and turning it into
a compound known as amebocyte lysate, which
is now a standard compound to detect bacterial
contamination in surgical instruments
and/or in your body fluids. And I can tell you that if you
ever had any kind of a surgery, or given any kind
of an injection, your life was probably saved,
or at least helped to be saved, by horseshoe crabs. So be mindful of that. So next time you
walk on the beach and you see a horseshoe crab
flailing its little arms and trying to turn
over, help it. Because he already helped you. So this is what I
would like to end with. I urge you to explore
the world around you. It’s just absolutely
full of these fantastic ancient, ancient organisms. And if you have a
chance, go to Delaware on the new moon or full
moon in May and June, and you may witness a
fragment of the world as it probably appeared
about 150 million years ago. Thank you very much. [APPLAUSE]

Comments 2

  • Piotr Naskrecki is a scientist who counts among the best. He has also a great role in the restoration of Gorongosa NP!

  • Thank you Piotr Nasckrecki for sharing your great passion of conservation and preservation of Biodiversity! thank you also to be very actively part of the rebirth of Gorongosa NP in Mozambique!

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