Why Were Triassic Animals so Weird?
Summary
TLDRThis video delves into the peculiar creatures of the Triassic period, exploring why they were so unique. It discusses the aftermath of the Permian mass extinction, which left many ecological niches vacant, prompting an adaptive radiation among the surviving reptiles. The Triassic's climate was ideal for cold-blooded animals, leading to the rise of diverse reptilian groups, including early dinosaurs. The script also corrects previous misconceptions about the noodle lizard, Tanystropheus, and ponders the fate of these strange creatures in light of the subsequent Triassic extinction event.
Takeaways
- 🐉 Archosaurs are a group of reptiles that first appeared in the late Permian period and diversified into various groups including crocodilians, pterosaurs, and dinosaurs.
- 🌿 The Triassic period saw the emergence of many unusual animals, partly due to the vast number of vacant ecological niches following the Permian mass extinction.
- 🦕 Dinosaurs, although present in the Triassic, were not the dominant life forms and shared the landscape with other large reptiles.
- 🦎 The 'noodle lizard' Tanystropheus is now believed to have been a shallow water predator, contrary to previous assumptions about its habitat.
- 🌋 The Triassic extinction event, while not as well understood as others, is thought to have been triggered by intense volcanic activity and subsequent climate changes.
- 🌎 The breakup of Pangaea and the resulting volcanic activity led to significant environmental changes, causing another mass extinction and the rise of dinosaurs.
- 🐊 Crocodilians, pterosaurs, and birds are well-known surviving members of the archosaur clade, indicating their adaptability and success.
- 🦖 The first dinosaurs were generalist carnivores and omnivores with an upright bipedal stance, which made them more energy-efficient.
- 🌿 The recovery of life after the Permian extinction led to an explosion of adaptive radiation, resulting in a variety of unique and strange creatures.
- 🌄 The end of the Triassic period marked the beginning of the 'Age of Dinosaurs,' where they expanded to fill the ecological niches left vacant by the extinct creatures.
- 🌿 The concept of adaptive radiation and the rise and fall of species due to mass extinctions is a recurring theme in Earth's history, highlighting the importance of adaptability in survival.
Q & A
What is an archosaur?
-Archosaurs are a clade of reptiles that first evolved during the late Permian. They diversified into many different groups during the Triassic, including crocodilians, pterosaurs, and dinosaurs. Birds are also considered members of this clade.
Why were the animals during the Triassic period considered strange?
-The animals of the Triassic period were considered strange due to their unique and diverse designs that do not resemble any living animals today. This was a time of great evolutionary experimentation as species adapted to fill the many vacant ecological niches left by the Permian mass extinction.
What was the significance of the Triassic period for reptilian evolution?
-The Triassic period was a time of significant evolutionary diversification for reptiles. With many ecological niches vacant due to mass extinction, reptiles evolved into a wide variety of forms, leading to the rise of groups like dinosaurs, pterosaurs, and crocodilians.
How did the Permian mass extinction impact the biodiversity during the Triassic period?
-The Permian mass extinction wiped out 90% of life on Earth, leaving many ecological niches vacant. This allowed the surviving species to rapidly evolve and diversify, leading to an era of unique and bizarre animals, often referred to as the 'Triassic freak show'.
What is adaptive radiation and how does it relate to the Triassic period?
-Adaptive radiation is a process by which a group of organisms rapidly evolves to fill multiple ecological niches, leading to the emergence of diverse forms. During the Triassic period, the mass extinction event created numerous vacant niches, prompting a rapid adaptive radiation among the surviving reptiles.
What is the current understanding of the Tanystropheus, also known as the 'noodle lizard'?
-Recent analysis, including digital reconstructions of the skull and fossil evidence, suggests that the Tanystropheus was likely a shallow water predator. It had interlocking teeth suitable for a fish diet and may have used its hind limbs in a frog-like manner for locomotion.
Why did some Triassic reptiles become extinct while dinosaurs thrived?
-The Triassic extinction event, possibly caused by intense volcanic activity and subsequent climate changes, led to the death of about 75% of life, including many of the strange reptiles. Dinosaurs, being more generalist and adaptable, were better positioned to survive these changes and eventually took over the vacant ecological niches.
How did the climate of the Triassic period influence reptilian evolution?
-The Triassic period had a climate more suitable for cold-blooded animals, which likely contributed to the success and diversification of reptiles. The favorable conditions allowed for a rapid recovery of biodiversity and the evolution of many unique reptilian forms.
What is the 'great dying' and how did it set the stage for the Triassic period?
-The 'great dying' refers to the Permian-Triassic extinction event, which was the most severe extinction event in Earth's history. It left the planet with a vast number of vacant ecological niches. From the surviving species, a diverse array of reptiles, including the first dinosaurs, evolved to fill these niches during the Triassic period.
What evidence suggests that the early dinosaurs were not the top predators during the Triassic?
-Fossil evidence, such as the skull of Herrerasaurus with bite marks, suggests that early dinosaurs coexisted with other large predators and may not have been at the top of the food chain. They likely competed with other archosaurs for resources and dominance.
How do mass extinctions influence the perception of 'weird' animals in the fossil record?
-Mass extinctions often lead to adaptive radiations, resulting in the evolution of many unique and unusual forms. These animals may seem strange to us because they evolved in response to specific environmental conditions that no longer exist, and many did not survive subsequent extinction events.
Outlines
🐉 Introduction to Triassic Animals and Archosaurs
The video begins by revisiting the peculiar creatures of the Triassic period, highlighting the presenter's favorites and addressing the question of why these animals were so strange. It transitions into a discussion about 'archosaurs,' a group of reptiles that first appeared in the late Permian and diversified into groups like crocodilians, pterosaurs, and dinosaurs. The presenter clarifies that while some successful Triassic animals were not archosaurs, they were still part of the reptile family tree. The video also corrects a previous statement about the 'noodle lizard,' now believed to have been a shallow water predator, and emphasizes the uniqueness of Triassic reptiles compared to modern ones.
🌿 The Aftermath of the Permian Extinction and Adaptive Radiation
This segment delves into the aftermath of the Permian mass extinction, which wiped out 90% of life on Earth. The presenter explains how the few surviving species filled the vacant ecological niches, leading to an explosion of biodiversity known as adaptive radiation. The Triassic period's climate was particularly conducive to cold-blooded animals, allowing reptiles to diversify into a variety of forms. The video discusses the rise of archosaurs, including the first dinosaurs, and how they competed with other large reptiles. It also touches on the mysterious Triassic extinction event and how it led to the dinosaurs eventually taking over.
🔥 The Triassic Extinction and the Dawn of the Age of Dinosaurs
The final paragraph discusses the Triassic extinction event, which is less understood than other mass extinctions. The presenter outlines various theories, including a possible impact and intense volcanic activity, which could have caused significant environmental changes. The video concludes by reflecting on the cyclical nature of mass extinctions and adaptive radiations, questioning whether our perception of 'weird' animals is due to their difference from what we're accustomed to. It ends with a tongue-in-cheek remark about human exceptionalism and our ability to avoid the fate of past species.
Mindmap
Keywords
💡Triassic Period
💡Archosaurs
💡Tanystropheus
💡Permian Mass Extinction
💡Adaptive Radiation
💡Draconosaurs
💡Herrerasaurus
💡Triassic Extinction Event
💡Specialization
💡Biodiversity
Highlights
Exploration of bizarre animals from the Triassic period.
Discussion on why animals during the Triassic were so strange.
Definition and explanation of what archosaurs are.
Correction about the noodle lizard's habitat and swimming ability.
The impact of the Permian mass extinction on the biodiversity of the Triassic period.
Adaptive radiation as a response to mass extinctions and its role in the evolution of unique species.
How the climate of the Triassic period favored the evolution of cold-blooded animals.
The rise of the first dinosaurs and their competition with other large archosaurs.
Theories on the causes of the Triassic extinction event.
The effect of volcanic activity on the climate and ecosystems during the Triassic period.
The decline of specialized reptiles and the rise of dinosaurs post-Triassic extinction.
Reflection on how our perception of 'weird' animals is shaped by their rarity and unfamiliarity.
The potential for the continuation of the 'Triassic freak show' had the extinction event not occurred.
The beginning of the Age of Dinosaurs following the Triassic extinction.
Irony in human specialization and the potential for repeating historical patterns of extinction.
Transcripts
[Music]
so last week we explored the absolutely
bizarre animals that existed during the
triassic period i talked about some of
my favorites or the ones that stood out
to me for one reason or another but as i
researched this topic one question
started to come up time and again why
were these animals so strange what was
it about this time in particular that
led to so many wild designs in nature
but before i get into that topic i want
to start by giving a little bit of an
explanation to a question i got several
times in response to my last video
so what exactly is an archosaur
archosaurs are a clade of reptiles that
first evolved during the late permian as
we've discussed they diversified into
many different groups during the
triassic groups like crocodilians
pterosaurs and dinosaurs and by proxy
birds are the most well-known members of
this clade but during this 50 million
year heyday they literally took over the
world and although some of the different
triassic success stories weren't
actually members of the archosaurs like
our long neck boy tennie strophius and
the reptilian platypus drapanosaurus but
in general these were all branches of
the reptile family tree and the simplest
way i can put it is that today when
people think of reptiles we think of
lizards snakes turtles and crocodilians
well during the triassic there were many
other kinds of reptile that didn't fit
into any of these boxes
because even if i try to make
comparisons to living animals
the fact is this is not like anything
alive today and while we're on the
subject of tanis trophy is
i would like to make a correction to
what i said about the noodle lizard last
week i said that there was almost no
chance that this animal lived in an open
marine environment because of its small
limbs that would not have been very
useful for swimming this however is no
longer thought to have been the case now
as i said this animal is no stranger to
being the subject of scientific debate i
seriously feel like i could make an
entire video just about the different
ways that we've perceived this animal
over the years but the most recent
analysis comes from a digital
reconstruction done of the skull
that shows that the nostrils were
positioned on top of the skull this
along with learning that the teeth were
interlocking in the front like many
other animals that survive on a diet of
fish and finding fossils that suggest
that it may have been able to use its
hind limbs kind of similar to a frog
have led many to conclude that this
animal probably did live in the water
most of the time though still capable of
getting around on land it's now believed
that tannie strophius was probably a
shallow water predator i want to thank
tracy ford for providing me with the
picture of what this creature's skull
probably looked like in life but now
with that out of the way it's time for
us to tackle the bigger question and to
do that i think the best thing to do is
start at the beginning
one thing to remember about the history
of life on earth is that there are three
major eras that multicellular life has
existed and the first two have been
punctuated by world ending catastrophes
the most famous of these was 66 million
years ago when a meteor struck the
yucatan peninsula the results of this
impact was the complete decimation of
nearly every marine and terrestrial
ecosystem and the extinction of roughly
76 of all of earth's species now this is
the most famous extinction for two
reasons for one it's the extinction that
ended the age of the non-avian dinosaurs
and for two
it's the extinction that gave us and the
rest of the mammals the opportunity we
were looking for mammals did exist
throughout the mesozoic but like the
early dinosaurs in the triassic we were
unable to become the dominant life forms
on the planet until the old masters got
out of the way but despite how well
known this extinction is it was
definitely not the worst thing to ever
happen to life on earth if you go back
to the earliest days of the triassic you
would see a wounded world on the brink
of total collapse the permian mass
extinction wiped out literally 90 of the
life on earth this would be the closest
earth would ever come to becoming a dead
world but luckily a few species did
survive this great dying it was from
this handful of survivors that would
spawn the triassic freak show you see
pretty much every dominant niche from
the permian was left vacant because
literally every single animal filling
those roles was now extinct and as i've
said all the way back in my very first
video and probably several times since
then when an ecosystem stays the same
for a long time the specialists tend to
do well thus they keep becoming more
specialized to whatever it is that they
were doing so they can remain on top but
when conditions change
they often struggle to roll with the
punches and adapt now the details of
this extinction are an interesting topic
in itself and i have to really struggle
not to go off on a tangent about it and
make this video over an hour long which
i wouldn't mind doing but then i
definitely couldn't get it out to you
guys by friday so today we need to focus
on the 10 that did survive the permian
extinction because whenever there's a
lot of open niches caused by mass
extinctions there is kind of a power
vacuum where animals seem to quickly
evolve to fill those roles and gain
dominance this can lead to evolution
taking designs in very interesting
directions for instance a group of
monitor lizard-like archosaurs evolving
a disproportionately large head and with
it comes a stronger bite force and a
coveted spot as an apex predator this
process is called adaptive radiation and
with 90 percent of the life removed it
didn't take long for the survivors to
start evolving into all sorts of weird
and wonderful forms until the
biodiversity had built back up to a
healthy amount this was sped up even
more by the fact that the climate of the
triassic was much more well suited to
cold-blooded animals so basically from
the ashes of the great dying the stage
was set perfectly for the reptiles to
take over the world and simply by taking
advantage of it they inevitably
diversified into all sorts of bizarre
animals
so as life recovered from the permian
extinction the reptiles evolved into
many different groups that were
progressively getting more and more out
there this is when we started seeing
things like draponosaurus and
hyperodapadon along with another branch
of the archosaur family tree that
remained pretty small until the very
tail end of the period there were mostly
generalist carnivores and omnivores with
an upright bipedal stance and specially
adapted hip bones that made upright
locomotion easier and more energy
efficient these were the very first
dinosaurs and although a few species
like herrerasaurus became major
predators in the late triassic they
still likely weren't the top predators
especially considering herrerasaurus
actually lived in the same place as many
large archosaurs which means this
20-foot long carnivore probably wasn't
the king in fact the skull of
herrerasaurus has been found with bite
marks on it and it's unclear whether
these marks came from another
herrerasaurus or something else maybe
these early dinosaurs and the massive
archosaur
competed the same way that we see
different large predators do today so
even though the dinosaurs weren't on top
just yet they certainly weren't confined
to the shadows like the mammals during
the mesozoic they just could never reach
the level of dominance that they would
later because of competition from other
reptiles so if the dinosaurs didn't take
control and drive these other strange
creatures to extinction how did we end
up with so few of these animal groups
that were once so successful around
today
the triassic extinction event is
something that isn't as well understood
as the cretaceous or permian events
there are a few theories about what
exactly happened some involving a
possible impact adding to things even
though no crater of an extinction event
causing size has ever been dated to this
time
so the most popular theory is that it
all started with an intense jump in
volcanic activity as pangaea started to
rip apart and well
big changes in that often lead to a
domino effect it can mess with the
climate by adding greenhouse gases to
the atmosphere it can block out the sun
and disrupt the food web by stopping
photosynthesis and it can lead to acid
rain which can in turn acidify the
oceans apparently all these things were
happening even as the very land
underneath these animals feet was
literally falling apart this is a lot of
change and well stop me if i sound like
a broken record the generalist reptiles
that managed to survive the permian
extinction had now just spent the past
50 million years becoming specialists
themselves the strategy served them well
up until around 201 million years ago it
just inevitably couldn't last forever as
a result of these events around 75
percent of life would die out again
among them would be most of the strange
reptiles like the drapanosaurs the
wrinkasaurs the phytosaurs
and a lot of the large carnivorous
archosaurs and this time it would be the
dinosaurs that would step in to take
their place and now that i think about
it
is this really any stranger than this
or this
maybe we just perceive these animals as
weird because they're different than
what we're used to looking at but the
truth is every time that there's a drop
in biodiversity we see an explosion of
adaptive radiation shortly after and the
results are often things that we might
call weird they may seem particularly
strange to us today
because this time was literally
sandwiched in between two big mass
extinctions many of these animals
evolved to survive the triassic and the
better majority of them didn't make it
past that time so maybe had the triassic
extinction never happened
maybe we wouldn't see these animals as
weird because we would be used to seeing
them both in the fossil record as well
as possibly even alive today but
unfortunately for the strange
specialized animals of this time
it did happen and in my opinion this is
the moment when the age of dinosaurs
truly began when the generalist triassic
dinosaurs managed to last through the
volcanic armageddon that happened 201
million years ago they would inevitably
expand into the vacant niches again
becoming the rulers of earth until their
number would come up at the end of the
cretaceous this is a story as old as
time and history seems to be bound to
repeat itself over and over again
that is until it came to be our turn
because we humans are special we know
better than to become too specialized to
a certain way of life and even as we
become increasingly dependent on
technology and more and more fragile
systems and we actually make changes to
the world that might harm our current
way of life in the future you can all
sleep easy knowing that we humans cannot
possibly fall victim to the exact same
thing that has literally claimed 99
of all species that have ever lived on
this planet
see y'all next week everybody
[Music]
[Music]
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