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Siberian Neanderthal DNA Rewrites Human Evolution
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Aug 9, 2025
The sequencing of Siberian Neanderthal DNA, particularly from the Chagyrskaya Cave specimen known as Chagyrskaya 8, has significantly altered our understanding of Neanderthal history and their interactions with other ancient human groups. Found near Denisova Cave—home to both Denisovans and earlier Neanderthals—Chagyrskaya 8 dates to roughly 80,000 years ago and is genetically closer to later European Neanderthals, like the Vindija woman from Croatia, than to the older Altai Neanderthal from the same region. This suggests that Neanderthal populations migrated eastward from western Eurasia into Siberia, replacing or mixing with earlier groups. Genetic evidence also connects Chagyrskaya 8 to Denisova 11, a first-generation hybrid with a Denisovan father and a Neanderthal mother related to the Chagyrskaya population, indicating complex interbreeding patterns. Despite their presence across Eurasia, Neanderthals lived in extremely small, isolated communities—often fewer than 60 individuals—making them vulnerable to extinction. While all non-African humans today carry some Neanderthal DNA, the genetic contributions vary by population, with later Neanderthals like those from Vindija Cave leaving a stronger imprint. These findings, along with new insights into Neanderthal brain development, disease-related genes, and beneficial traits that persist in modern humans, reveal a far more dynamic, interconnected, and regionally diverse Neanderthal world than previously thought. Here are the direct links to the references I mentioned: High-quality genome from a Siberian Neanderthal (Chagyrskaya 8) https://pubmed.ncbi.nlm.nih.gov/32546518/ https://www.pnas.org/doi/abs/10.1073/pnas.2004944117 First-generation Neanderthal–Denisovan hybrid (Denisova 11) https://www.nature.com/articles/s41576-018-0054-6 Small, isolated Neanderthal populations & inbreeding https://pubmed.ncbi.nlm.nih.gov/25487326/ https://en.wikipedia.org/wiki/Neanderthal_genetics
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0:01
Neanderthalss and denisovvens were our
0:03
closest ancient human relatives before
0:05
they went extinct. These fascinating
0:07
groups interbred with early modern
0:09
humans, leaving behind a genetic legacy
0:12
that still lingers in people today. If
0:15
your ancestors came from outside Africa,
0:17
you likely carry a small percentage of
0:19
Neanderthal DNA. While some Asian and
0:23
Oceananian populations also have traces
0:26
of Dennisovven ancestry, this genetic
0:29
mixing tells us that when our ancestors
0:31
migrated from Africa, they met and
0:34
mingled with these ancient cousins. Yet,
0:37
despite their importance, we're still
0:39
piecing together the Neanderthal genetic
0:41
story. Scientists have only managed to
0:44
sequence five Neanderthal genomes so
0:46
far, and most are frustratingly
0:49
incomplete.
0:50
While we have some genetic material from
0:53
key sites like Vindiger cave in Croatia
0:55
and Mesmekaya cave in the Caucuses,
0:58
these sequences lack detail.
1:01
Even with additional fragments recovered
1:03
from Spanish and Croatian specimens, the
1:06
limited and often lowquality data,
1:09
especially from central regions where
1:10
Neanderthalss thrived, leaves big gaps
1:13
in our understanding of their genetic
1:15
history and their lasting impact on
1:18
modern humans. So far scientists have
1:21
successfully sequenced highquality
1:23
genomes from only a few ancient
1:25
individuals. Two Neanderthalss and one
1:28
Dennisovven.
1:30
The first Neanderthal genome comes from
1:32
Vindiger cave in Croatia and is often
1:35
referred to as the Croatian Neanderthal.
1:38
The second known as the Alaii
1:40
Neanderthal or Dennisova 5 was found in
1:43
Dennisova Cave in Siberia's Alai
1:46
mountains. Discovered in Dennisova Cave,
1:49
Siberia, Dennisova 5 lived approximately
1:52
between 120,000 to 90,000 years ago,
1:56
making it one of the oldest highquality
1:58
Neanderthal genomes sequenced. Genetic
2:01
analysis reveals that this individual
2:03
belonged to an early Neanderthal
2:06
population that was more distantly
2:08
related to later European Neanderthalss,
2:10
including those from Vindiger Cave.
2:13
Unlike later Neanderthalss, Denisova 5
2:16
shows lower genetic contributions to
2:18
modern humans, suggesting its group had
2:21
limited contact with early homo sapiens.
2:24
Interestingly, Denisova 5 was found in
2:27
the same cave as the Denisovans, an
2:29
entirely different archaic human group.
2:33
This indicates that Siberia was a
2:35
contact zone where multiple homminin
2:37
species including Neanderthalss and
2:39
Denisvens coexisted and occasionally
2:42
interbred. The Vindiger Neanderthalss
2:45
from Croatia lived much later around
2:48
52,000 to 44,000 years ago. Their
2:52
genomes show that they were part of a
2:54
later, more derived Neanderthal
2:56
population that had replaced or mixed
2:58
with earlier groups like the Ali
3:00
Neanderthalss.
3:02
Vindiger Cave in Croatia was one of the
3:04
last known habitats of Neanderthalss
3:07
before their extinction. The cave
3:09
contains numerous bone fragments, many
3:12
too damaged to identify by appearance
3:15
alone.
3:16
However, the site has exceptionally
3:18
wellpreserved ancient DNA, allowing
3:21
researchers to extract genetic material
3:24
not only from Neanderthalss, but also
3:26
from pleaene era animals like cave
3:29
bears. Unlike Dennisova 5, the Vindiger
3:33
Neanderthalss contributed significantly
3:35
more DNA to modern humans, about 1.8 to
3:39
2.6% of non-African genomes today. This
3:44
suggests they were among the last
3:45
Neanderthalss to interact with early
3:47
modern humans before going extinct.
3:50
Their genetic legacy is strongest in
3:52
East Asians, possibly due to later
3:54
population movements. One of the most
3:57
surprising discoveries came from a bone
3:59
fragment in Denise of a cave belonging
4:02
to Dennis over 11, a young girl whose
4:05
DNA showed she had a Neanderthal mother
4:07
and a Denisven father. Even more
4:10
intriguing, her Neanderthal mother was
4:12
genetically closer to the Croatian
4:14
Neanderthal than to the Al Thai
4:16
Neanderthal.
4:18
This finding suggests that at some point
4:20
a different group of Neanderthalss
4:22
migrated into the Alai region, replacing
4:25
or mixing with the earlier population.
4:28
Such interactions highlight the complex
4:30
movements and relationships between
4:32
ancient human groups. To further explore
4:35
these dynamics, scientists recently
4:37
sequenced the complete genome of a
4:39
Neanderthal from Chagiskaya cave located
4:43
near Dennisova cave. This new genome
4:46
helps researchers better understand the
4:48
Neanderthal population structure,
4:51
migration patterns, and genetic
4:53
adaptations.
4:54
By comparing these ancient genomes with
4:57
modern human DNA, scientists can uncover
5:00
how interbreeding influenced our
5:02
evolution.
5:03
The Chagerskaya 8 Neanderthal discovered
5:06
in a Siberian cave in 2011 represents an
5:10
important piece of the puzzle in
5:12
understanding ancient human history.
5:14
Scientists extracted DNA from just 50 mg
5:17
of bone powder, revealing remarkably
5:20
wellpreserved genetic material with
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minimal contamination from modern
5:24
humans. This pristine preservation
5:27
allowed researchers to sequence a
5:29
highquality genome, providing
5:31
unprecedented insights into this
5:33
individual's life and relationships.
5:36
The success of this extraction
5:38
demonstrates how advances in ancient DNA
5:40
technology continue to revolutionize our
5:43
understanding of prehistoric
5:45
populations.
5:47
Dating this Neanderthal proved
5:49
particularly interesting as different
5:51
methods produced slightly conflicting
5:54
results. Genetic analysis suggested
5:56
Chagiskaya 8 lived approximately 80,000
6:00
years ago, placing it between two other
6:02
well-known Neanderthalss. The older
6:04
Alaii specimen about 110,000 years old,
6:09
and the more recent Croatian individual
6:11
sediment layer indicated a younger age
6:13
of about 60,000 years. This discrepancy
6:17
could result from various factors,
6:19
including potential movement of the bone
6:21
within the cave deposits over millennia
6:23
or limitations in our current dating
6:25
techniques. Genetic comparisons revealed
6:28
fascinating connections between Chagaya
6:31
8 and other ancient humans. This
6:34
individual showed closer ties to
6:36
European Neanderthalss like Croatian
6:39
individual Vindiger Cave than to earlier
6:42
Siberian populations, suggesting a
6:45
westward migration at some point in
6:47
Neanderthal history. Most remarkably,
6:50
Chagoskaya 8 shared significant genetic
6:53
similarity with the famous hybrid
6:55
Denisovven 11, whose mother came from a
6:58
Neanderthal population closely related
7:00
to European groups.
7:03
This connection provides compelling
7:05
evidence for multiple waves of
7:06
Neanderthal expansion across Eurasia and
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complex interactions between different
7:12
ancient human groups. The study of
7:14
Chagaskkaya 8 also shed new light on the
7:17
genetic legacy of Neanderthalss in
7:19
modern humans. While all non-African
7:22
populations today carry some Neanderthal
7:24
DNA, this particular individual
7:27
contributed less to modern human genomes
7:30
than the later Vindiger cave
7:31
Neanderthal.
7:33
This finding suggests that different
7:35
Neanderthal populations interacted with
7:37
our ancestors to varying degrees, with
7:40
some groups leaving a more substantial
7:42
genetic imprint than others. The reasons
7:45
behind these differences remain unclear,
7:47
but may relate to timing, geography, or
7:50
cultural factors influencing
7:52
interbreeding opportunities. To
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investigate potential regional
7:56
variations in Neanderthal ancestry,
7:59
researchers examined hundreds of modern
8:01
genomes from across Eurasia and
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Oceanania. Surprisingly, they found no
8:06
evidence that Chagaskkaya 8's population
8:09
contributed uniquely to any present-day
8:12
group. Instead, the genetic data
8:14
suggests that the Neanderthalss who
8:16
interbred with our ancestors were
8:18
broadly similar to both Chagirkaya ate
8:21
and the Vindiger woman, representing a
8:24
related but more successful branch of
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the Neanderthal family tree. These
8:29
findings paint a complex picture of
8:31
ancient human interactions where some
8:33
Neanderthal groups thrived while others
8:36
left only faint traces in the
8:38
archaeological record. The Vindiger
8:40
woman lived 52,000 years ago. The Alai
8:44
Neanderthal 122,000 years ago, the
8:48
Chagaya 8 individual approximately
8:50
80,000 years ago and the Dennisovven
8:54
72,000 years ago. These dates reveal a
8:58
chronological sequence where the Ali
9:00
Neanderthal represents the earliest
9:02
population followed by the Dennisovven
9:05
then Chagaraya 8 and finally the
9:08
Vindiger individual. Genetic comparisons
9:11
show Neanderthalss and Denisovvens split
9:14
between 390 and 440,000 years ago while
9:18
Neanderthalss and modern humans diverged
9:21
between 520 and 630,000
9:24
years ago. The Vindiga and Alai
9:26
Neanderthal population separated between
9:29
130 and 145,000 years ago with
9:33
Chigoskaya 8 showing an intermediate
9:35
divergence time of about 100,000 years
9:39
from the Vindiger lineage. This places
9:41
Chaskkaya 8 as part of a later
9:44
Neanderthal population that was more
9:46
closely related to European
9:47
Neanderthalss like Vindiger than to the
9:50
older Alaii group yet still maintained
9:53
some distinct genetic characteristics.
9:56
The Chagar skaya 8 Neanderthal is
9:58
genetically closer to the Croatian
10:00
Neanderthal and other late Neanderthalss
10:02
from Western Eurasia than to Dennisova
10:05
5, an older Neanderthal who lived in the
10:07
Alai mountains. This suggests that some
10:10
Neanderthal groups from western Eurasia
10:13
migrated eastward into Siberia between
10:15
120,000
10:17
and 80,000 years ago. The tools found in
10:20
Chagarskia cave are similar to those
10:23
from central and eastern Europe,
10:25
indicating that these Neanderthalss
10:27
brought their toolmaking traditions with
10:29
them. During this eastward movement,
10:31
they also encountered local Denisovven
10:33
groups as seen in Denisover 11, a child
10:36
with a Denisovven father and a
10:38
Neanderthal mother related to Chagar
10:40
Skaya 8's group. Early modern humans
10:43
were likely interbred with Neanderthalss
10:46
before the Vindiger Alai split around
10:49
145,000 years ago. The Vindiger genome
10:52
shows no evidence of separate modern
10:54
human interbreeding, suggesting all such
10:57
mixing occurred before European and
10:59
Siberian Neanderthalss diverged.
11:02
This indicates interbreeding was
11:04
probably common among many pleaene human
11:06
groups. The Chagaya 8 Neanderthal from
11:10
Siberia reveals fascinating connections
11:13
between different Neanderthal groups.
11:15
While found in the same region as the
11:17
much older Denisova 5 specimen, its DNA
11:21
shows stronger ties to later European
11:24
Neanderthalss like the Vindiger woman.
11:27
This suggests significant population
11:29
movements across Eurasia with later
11:32
groups replacing or mixing with earlier
11:34
ones. The genetic links become
11:37
particularly interesting when examining
11:39
relationships with Denisven. Trigger
11:41
skaya 8 shares fewer genes with the
11:43
Dennisova 3 individual than Dennisova 5
11:46
does but shows closer connections to
11:49
Denisova 11, a first generation
11:51
Neanderthal Denisven hybrid. This
11:54
indicates Chagga Skaya 8 may have been
11:57
closely related to Denisva 11's
11:59
Neanderthal mother, demonstrating
12:01
complex interbreeding patterns between
12:04
these ancient human groups. Modern
12:06
humans outside Africa carry Neanderthal
12:09
DNA, a legacy of interbreeding that
12:12
occurred 50,000 90,000 years ago. Both
12:16
Chagoskaya 8 and the Vindiger woman
12:19
contributed similarly to modern human
12:21
genetics, though detailed analysis
12:24
suggests the Vindiger population may
12:26
have played a slightly larger role in
12:28
shaping our DNA. When examining only the
12:32
Neanderthal derived segments in modern
12:34
humans, the Vindiger group's genetic
12:36
influence appears somewhat stronger.
12:39
However, broad comparisons across
12:40
populations in Asia, Europe, India, and
12:43
Oceanania show no significant difference
12:46
in how much DNA they share with either
12:49
Shagirkaya 8 or the Vindiger woman.
12:52
Neanderthal ancestry comes from
12:54
populations related to Vindiga Mesmmya
12:58
rather than the Ali lineage. All studied
13:01
Neanderthalss show signs of living in
13:03
extremely small isolated communities.
13:06
The Dennis over 5 individual reveals
13:09
severe inbreeding with long stretches of
13:12
identical DNA indicating closely related
13:14
parents. Chagga Skaya 8 shows less
13:17
extreme but still significant inbreeding
13:20
patterns while the Vindiger woman's DNA
13:22
suggests a slightly larger though still
13:25
very small population size. Computer
13:29
models estimate Siberian Neanderthalss
13:31
lived in groups of fewer than 60
13:33
individuals dramatically smaller than
13:36
contemporary Dennisovven and modern
13:38
human communities that numbered over
13:40
100. This might also be because the Alai
13:43
region was on the edge of the
13:45
Neanderthalss range and was likely more
13:47
heavily populated by Dennisovvens.
13:50
These patterns suggest Neanderthal
13:52
groups frequently existed as small,
13:55
vulnerable populations. These tiny
13:57
population sizes likely contributed to
14:00
Neanderthals's eventual extinction.
14:02
Scientists examined nearly 1,000
14:05
significant genetic changes across 889
14:09
Neanderthal genes that could affect
14:11
protein function along with thousands of
14:13
other variations. Surprisingly, none of
14:16
these changes clustered in particular
14:18
biological systems or functions. This
14:21
suggests that while Neanderthalss
14:23
accumulated many genetic differences
14:25
from modern humans, these didn't create
14:28
dramatically different biological
14:30
capabilities. The findings paint a
14:32
picture of Neanderthalss as numerous
14:35
small isolated groups with limited
14:37
genetic diversity, occasionally mixing
14:40
with each other and other human species,
14:42
but ultimately unable to maintain
14:44
sufficient population sizes to survive
14:47
alongside expanding modern humans. The
14:50
medical implications of Neanderthal DNA
14:53
are significant. The Vindiger genome
14:55
helps identify more disease related
14:58
variants inherited from Neanderthalss,
15:00
including associations with cholesterol
15:02
levels, vitamin D metabolism, eating
15:05
disorders, fat distribution, rheumatoid
15:08
arthritis, schizophrenia, and immune
15:11
responses. These findings demonstrate
15:14
how Neanderthal DNA continues to
15:17
influence human health, particularly
15:19
affecting neurological, psychiatric, and
15:22
immunereated traits in modern
15:24
populations. The Vindiger genome
15:26
provides unprecedented power to study
15:29
these ancient genetic contributions to
15:31
contemporary disease risks. Researchers
15:34
studying Neanderthal DNA made an
15:36
interesting discovery about how their
15:38
brains developed differently from ours.
15:41
They found that Neanderthal teenagers
15:43
had more genetic mutations in genes
15:45
active in the strriatum, a brain region
15:48
involved in movement and motivation,
15:51
compared to other brain areas. These
15:54
mutations affected both the proteins
15:56
themselves and the genetic switches
15:58
controlling when these genes turned on
16:00
and off. What's particularly notable is
16:03
that these strriatum related genes are
16:05
located in parts of the genome where
16:08
modern humans have very little
16:09
Neanderthal DNA, suggesting these
16:12
changes may have been harmful or
16:14
unhelpful to our ancestors and were
16:16
eventually eliminated through natural
16:18
selection.
16:20
The same pattern of genetic changes
16:21
wasn't seen equally across all brain
16:24
regions. While the strriatum showed the
16:26
most differences, other areas like the
16:29
posterior parietal cortex involved in
16:32
spatial reasoning, vententralateral
16:34
preffrontal cortex important for
16:36
decision making and somatoensory cortex
16:40
processes touch sensations also
16:43
displayed notable changes in their
16:44
regulatory DNA during prenatal
16:47
development. This suggests Neanderthal
16:50
brain development followed a somewhat
16:52
different genetic program than modern
16:54
humans, especially in regions
16:56
controlling movement and sensory
16:58
processing.
16:59
Interestingly, scientists also
17:01
identified 35 regions of the Neanderthal
17:04
genome that appear to have undergone
17:06
positive selection, meaning these
17:08
genetic changes were likely beneficial
17:10
and helped Neanderthals survive. These
17:13
selected regions include genes related
17:15
to brain development, immune system
17:18
function, wound healing, and energy
17:20
production in cells. Some of these
17:23
beneficial genetic changes overlap with
17:25
regions that also show signs of positive
17:27
selection in modern humans, indicating
17:30
both species may have independently
17:32
evolved similar advantageous traits in
17:34
these areas. This finding helps explain
17:37
why some Neanderthal DNA persists in
17:40
modern human populations. We likely kept
17:43
the helpful bits while discarding the
17:44
less compatible ones.
17:48
[Music]
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