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The Theory of the Last Universal Common Ancestor LUCA

Saalbach, Klaus · 2026

Abstract

This working paper provides a brief introduction to the Last Universal Common Ancestor LUCA and the potential biosafety implications. LUCA is the hypothetical precursor of all modern cells, i.e., the Archaea, the Prokaryotes and Eukaryotes (which are the common ancestor of bacteria, animals, fungi, and plants). LUCA’s properties and timeframe of existence are relevant for the past, i.e., the origin of life, but also for the future, i.e., the question whether the generation of completely synthetic life could be possible which would be a major biosafety issue. Currently, all modified and synthetic organisms including synthetic viruses could only be produced in already living environments (only life can create other life), i.e., there is a clear border between dead and living materials. In this decade, the LUCA research made substantial progress by utilizing rapidly growing genomic databases and enhanced analysis methods (computed molecular clock of gene development combined with evidence from microfossils). The generally accepted theory is that life started with interactions between ribonucleic acid (RNA) and amino acids which formed complexes for replication in a membrane, i.e., a physical border between cell and environment. This is also known as ‘RNA world’. Later, desoxyribonucleic acid (DNA) was integrated. Early eukaryotes integrated alphaproteobacteria into a permanent symbiosis (now as mitochondria in animals, chloroplasts in plants) which enhanced metabolism and allowed the development of multi-cellular organisms. However, in December 2025, a calculation of mutation rates showed that LUCA seemed to have existed already shortly after the creation of Earth and Moon which was caused by the collision of two proto-planets 4.5 billion years ago. Some researchers found hints that LUCA was already a quite complex organism with an early immune system against viruses. But as LUCA is the last cell, not the first one, additional time must be added for the appearance of the first universal common ancestor FUCA. But when adding this, there is very little to no time left (dependent on the mutation rate calculation) since creation of Earth and Moon. In 2025, experiments on the International Space Station ISS showed that Archaea, Fungi and Bacteria survived long-term exposure to open space. Even the space dust collected from the surface of the ISS contained biological objects. In addition, it was shown that non-enzymatic synthesis of peptides is possible in space. A study from 2025 found bacteria in ultra-sterile spacecraft-assembly NASA cleanrooms despite extreme conditions; another study that bacteria and their viruses and can adapt themselves to microgravity by co-evolution. These findings may indicate that biomolecules e.g., from asteroids could have enabled and accelerated the early phases of life on the young earth which was not protected by a thick atmosphere. Experiments to create synthetic cells were done with Mycoplasma mycoides which were engineered to minimal genome cells with the smallest possible genome that allows autonomous life and replication. These experiments showed that replication below a certain complexity almost completely stopped, i.e., no clues to a hypothetical simplified cell replication in an RNA world could be shown. However, the rapid advances of Artificial Intelligence (AI) in genome analysis and creation of natural and artificial proteins as well as the ability to analyze very large genomic data sets may bring a sudden breakthrough in the LUCA debate, both for the understanding of origin of life as well as for the complete synthesis of living cells which could cause major biosafety issues via infection, contamination, or misuse

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The Theory of the Last Universal Common Ancestor LUCA

Author: Saalbach, Klaus
Year: 2026
DOI: 10.48693/827
Source: https://osnadocs.ub.uni-osnabrueck.de/bitstream/ds-2026020114051/1/Theory_LUCA_2026_Saalbach.pdf
Theo y_LUCA 1
Apl. P o . D . D . K. Saalbach
Geos a egy and Geopoli ics
Depa men 1
49069 Osnab ueck
The Theo y o he Las Uni e sal Common
Ances o LUCA
02 Feb ua y 2026
Summa y
This wo king pape p o ides a b ie in oduc ion o he Las Uni e sal Common Ances o LUCA
and he po en ial biosa e y implica ions. LUCA is he hypo he ical p ecu so o all mode n cells,
i.e., he A chaea, he P oka yo es and Euka yo es (which a e he common ances o o bac e ia,
animals, ungi, and plan s). LUCA’s p ope ies and ime ame o exis ence a e ele an o he
pas , i.e., he o igin o li e, bu also o he u u e, i.e., he ques ion whe he he gene a ion o
comple ely syn he ic li e could be possible which would be a majo biosa e y issue.
Cu en ly, all modi ied and syn he ic o ganisms including syn he ic i uses could only be
p oduced in al eady li ing en i onmen s (only li e can c ea e o he li e), i.e., he e is a clea
bo de be ween dead and li ing ma e ials. In his decade, he LUCA esea ch made subs an ial
p og ess by u ilizing apidly g owing genomic da abases and enhanced analysis me hods
(compu ed molecula clock o gene de elopmen combined wi h e idence om mic o ossils).
The gene ally accep ed heo y is ha li e s a ed wi h in e ac ions be ween ibonucleic acid
(RNA) and amino acids which o med complexes o eplica ion in a memb ane, i.e., a physical
bo de be ween cell and en i onmen . This is also known as ‘RNA wo ld’. La e ,
desoxy ibonucleic acid (DNA) was in eg a ed. Ea ly euka yo es in eg a ed alphap o eobac e ia
in o a pe manen symbiosis (now as mi ochond ia in animals, chlo oplas s in plan s) which
enhanced me abolism and allowed he de elopmen o mul i-cellula o ganisms. Howe e , in
Decembe 2025, a calcula ion o mu a ion a es showed ha LUCA seemed o ha e exis ed
al eady sho ly a e he c ea ion o Ea h and Moon which was caused by he collision o wo
p o o-plane s 4.5 billion yea s ago. Some esea che s ound hin s ha LUCA was al eady a
qui e complex o ganism wi h an ea ly immune sys em agains i uses. Bu as LUCA is he las
cell, no he i s one, addi ional ime mus be added o he appea ance o he i s uni e sal
common ances o FUCA. Bu when adding his, he e is e y li le o no ime le (dependen
on he mu a ion a e calcula ion) since c ea ion o Ea h and Moon.
In 2025, expe imen s on he In e na ional Space S a ion ISS showed ha A chaea, Fungi and
Bac e ia su i ed long- e m exposu e o open space. E en he space dus collec ed om he
su ace o he ISS con ained biological objec s. In addi ion, i was shown ha non-enzyma ic
syn hesis o pep ides is possible in space. A s udy om 2025 ound bac e ia in ul a-s e ile
spacec a -assembly NASA clean ooms despi e ex eme condi ions; ano he s udy ha
bac e ia and hei i uses and can adap hemsel es o mic og a i y by co-e olu ion. These
indings may indica e ha biomolecules e.g., om as e oids could ha e enabled and
accele a ed he ea ly phases o li e on he young ea h which was no p o ec ed by a hick
a mosphe e.
Expe imen s o c ea e syn he ic cells we e done wi h Mycoplasma mycoides which we e
enginee ed o minimal genome cells wi h he smalles possible genome ha allows
au onomous li e and eplica ion. These expe imen s showed ha eplica ion below a ce ain
complexi y almos comple ely s opped, i.e., no clues o a hypo he ical simpli ied cell eplica ion
in an RNA wo ld could be shown. Howe e , he apid ad ances o A i icial In elligence (AI) in
genome analysis and c ea ion o na u al and a i icial p o eins as well as he abili y o analyze
e y la ge genomic da a se s may b ing a sudden b eak h ough in he LUCA deba e, bo h o
he unde s anding o o igin o li e as well as o he comple e syn hesis o li ing cells which
could cause majo biosa e y issues ia in ec ion, con amina ion, o misuse.
Theo y_LUCA 2
Con en
1 The LUCA Theo y .................................................................................................................................. 3
1.1 In oduc ion ................................................................................................................................... 3
1.2 The Concep o LUCA ..................................................................................................................... 3
1.2.1 The Ea ly Ea h ....................................................................................................................... 3
1.2.2 FUCA and LUCA ....................................................................................................................... 4
1.2.3 Recen indings ....................................................................................................................... 5
1.3 Minimal Genome Cells .................................................................................................................. 5
1.4 Findings in Ou e Space ................................................................................................................. 6
1.5 Po en ial Impac o A i icial In elligence ...................................................................................... 7
2 Summa y ............................................................................................................................................... 7
3 Re e ences ............................................................................................................................................ 8
Theo y_LUCA 3
1 The LUCA Theo y
1.1 In oduc ion
This wo king pape p o ides a b ie in oduc ion o he Las Uni e sal Common Ances o
LUCA and he po en ial biosa e y implica ions.
The Las Uni e sal Common Ances o LUCA is he hypo he ical p ecu so o all mode n cells,
i.e., he A chaea, he P oka yo es and Euka yo es (cells wi h a nucleus which a e he common
ances o o bac e ia, animals, ungi, and plan s). LUCA’s p ope ies and ime ame o exis ence
a e ele an o he pas , i.e., he o igin o li e, bu also o he u u e, i.e., he ques ion whe he
he gene a ion o comple ely syn he ic li e could be possible. Cu en ly, all modi ied and
syn he ic o ganisms including syn he ic i uses could only be p oduced in al eady li ing
en i onmen s (only li e can c ea e o he li e), i.e., he e is a clea bo de be ween dead and
li ing ma e ials.
In his decade, he LUCA esea ch made subs an ial p og ess by u ilizing apidly g owing
genomic da abases and enhanced analysis me hods.
While a s udy om Delaye e al. in 2005 was based on 20 genomes
1
, an analysis o Tobiasson
e al. 2026 could use he p ok2311 da abase om he Na ional Cen e o Bio echnology
In o ma ion (NCBI) GenBank o 75 million p oka yo ic p o ein sequences om 47,545
comple e p oka yo ic genomes and he EukP o .3 wi h 30 million euka yo ic sequences om
993 species
2
.
O iginally, he sea ch o po en ial LUCA genes and he age calcula ion was based on he sea ch
o common genes be ween he main lineages o li e, he A chaea, P oka yo es and Euka yo es.
The s udy o Moody e al. 2024 compu ed he p obabili y ha a gi en gene was p esen by
compa ing he eme gence o genes and species (gene ees o species ees), he in luence o
common mu a ions esea che s o ge a p obabili y o each gene o be pa o LUCA
3
esul ing
in 399 gene amilies ha encoded app oxima ely 2451 o 2855 p o eins
4
.
Fu he mo e, he age was es ima ed by a molecula clock, whe e he a e a which mu a ions
occu is es ima ed and hen he numbe o mu a ions is coun ed de e mine how much ime has
passed
5
. Bu in addi ion, he clock was c oss-checked agains mic o ossils as he ea lies
po en ial aces o biological li e on Ea h o align he calcula ion wi h geological e idence
6
.
1.2 The Concep o LUCA
1.2.1 The Ea ly Ea h
The sola sys em s a ed wi h he o ma ion o dus o small p o o-plane s caused by g a i y.
App oxima ely 4,510±10 million yea s ago, wo p o o-plane s collided, he p o o-Ea h Tellus
wi h a ma s-like objec called Theia
7
, a hesis which is suppo ed by geological indings on
Ea h and Moon which we e c ea ed by he collision. Geological e idence om mine als
indica es ha he Ea h cooled down o a con inen al c us wi h oceans app oxima ely 100 o
200 million yea s la e
8
which means ha li e could be heo e ically possible hen
9
. The i s
e a, he Hadean, con inued un il 4 billion yea s ago, ollowed by he A chean.
1
Delaye e al. 2024
2
Tobiasson e al. 2026
3
Lambe 2024
4
Goldman/Bece a 2024
5
S a 2024
6
Moody e al. 2024, Neukamm 2024
7
Moody e al. 2024
8
Goldman/Bece a 2024, Lambe 2024
9
Goldman/Bece a 2024
Theo y_LUCA 4
I was a gued ha li e could no su i e he Hadean because o he hypo he ical La e Hea y
Bomba dmen (LHB) app oxima ely 3.7 o 3.9 billion yea s ago by as e oids and celes ial bodies
coming om he Tellus-Theia collision
10
. Howe e , he ime ame o he LHB is unknown.
1.2.2 FUCA and LUCA
The gene ally accep ed heo y is ha li e s a ed wi h in e ac ions be ween ibonucleic acid
(RNA) and amino acids which o med complexes o eplica ion in a memb ane, i.e., a physical
bo de be ween cell and en i onmen . This is also known as ‘RNA wo ld’.
In he 1980ies, ca aly ic p ope ies o RNA we e disco e ed which led o he hypo hesis o an
RNA wo ld
11
. In his wo ld, RNA-based enzymes ( ibozymes) s a ed o bind amino acids
which hen esul ed in he o ma ion o RNA-p o ein complexes and he abili y o eplica e.
Un il oday, all cells syn hesize p o eins wi h ibosomes (RNA-p o ein complexes) which may
indica e ha he Fi s Uni e sal Common Ances o FUCA s a ed wi h a kind o ibosome wi h
an ea ly Pep idyl T ans e ase Cen e PTC which connec s amino acids o pep ides and p o ein
chains
12
. While his likely bu hypo he ical, he e is g owing e idence ha a lease he Las
Uni e sal Common Ances o LUCA al eady had ibosomes
13
.
Some poin s mus be aken in o conside a ion:
Maybe he e was no one FUCA; LUCA may ha e eme ged by ho izon al gene ans e be ween
ea ly li e o ms
14
. Also, i unlikely ha FUCA and LUCA we e alone. LUCA was p obably pa
o a la ge ecosys em, bu is he only cell whe e he successo s su i ed un il oday, while o he
li e o ms did no .
When and how i uses eme ged is unknown. The mos plausible hypo hesis is ha i uses
eme ged as spin-o s om e y ea ly li e o ms and since hen exis in a ne e -ending co-
e olu ion wi h hei hos cells. I was specula ed ha e o i uses may hen ha e in oduced
DNA in o ea ly cells which changed he RNA wo ld in o a DNA wo ld. DNA has he
e olu iona y ad an age o a highe s abili y han RNA.
The indings o Moody e al. 2024, ha LUCA al eady seemed o ha e a CRISPR/Cas (clus e ed
egula ly in e spaced sho palind omic epea s/CRISPR-associa ed p o ein) sys em o
iden i y and emo e i al sequences, suppo s he heo y ha i uses eme ged be o e LUCA.
The LUCA genome shows he impo ance o ibosomes, i.e., nucleic acid (RNA)-p o ein
complexes which d i e me abolism and o m he link be ween genes and p o ein syn hesis.
Meanwhile i was shown ha e en oday phospho us- ich lakes exis which would be ideal o
eme gence o such cells
15
.
In 1976, he esea che Woese analyzed ibosomal subuni s and disco e ed he a chaea as
sepa a e en i y
16
. A e decades o discussion he e is meanwhile g owing e idence om
genome da abase analyses ha LUCA de eloped o ea ly bac e ia and a chaea and ha
euka yo es eme ged om he Asga d subg oup o a chaea
17
. This subg oup in eg a ed
alphap o eobac e ia in o a pe manen symbiosis (now as mi ochond ia in animals, chlo oplas s
10
Moody e al. 2024
11
P osdocimi e al. 2019
12
P osdocimi e al. 2019
13
Moody e al. 2024
14
McClellan 2013, Delaye e al. 2024
15
Uni e si y o Washing on 2019
16
P osdocimi e al. 2019
17
Tobiasson e al. 2026
Theo y_LUCA 5
in plan s)
18
which enhanced me abolism and allowed he de elopmen o mul i-cellula
o ganisms
19
.
Figu e 1 p esen s a simpli ied summa y o he cu en heo ies.
1.2.3 Recen indings
Howe e , in Decembe 2025, a calcula ion o mu a ion a es showed ha LUCA seemed o
ha e exis ed al eady sho ly a e he c ea ion o Ea h and Moon which was caused by he
collision o wo p o o-plane s 4.5 billion yea s ago.
Moody e al. 2024 es ima ed ha LUCA li ed a ound 4.2 Ga, wi h a 95% con idence in e al
om 4.09 o 4.33 Ga.
20
Fu he mo e, hey ound hin s ha LUCA was al eady a qui e complex
o ganism wi h an ea ly immune sys em agains i uses. The es ima ed size o he LUCA
genome wi h 399 gene amilies ha encoded app oxima ely 2451 o 2855 p o eins shows an
o ganism wi h a simila complexi y o bac e ia. In a new analysis om Decembe 2025, Kay e
al. calcula ed an e en ea lie ime ame o LUCA o 4.50 Ga wi h a con idence in e al om
4.43 o 4.52 Ga) which would be di ec ly a e he p o o-plane collision
21
.
Bu as LUCA is he las cell, no he i s one, addi ional ime mus be added o he appea ance
o he i s uni e sal common ances o FUCA. Bu when adding his, he e is e y li le o no
ime le (dependen on he mu a ion a e calcula ion) since c ea ion o Ea h and Moon.
1.3 Minimal Genome Cells
Expe imen s o c ea e syn he ic cells we e done wi h Mycoplasma mycoides which we e
enginee ed o minimal genome cells wi h he smalles possible genome ha allows au onomous
li e and eplica ion. Howe e , hese expe imen s showed ha eplica ion below a ce ain
complexi y almos comple ely s opped, i.e., no clues o a hypo he ical simpli ied cell eplica ion
in an RNA wo ld could be shown.
The minimal genome is he smalles possible genome ha allows au onomous li e and sel -
eplica ion. Since 2010, C aig Ven e and his eam wo ked o de elop a minimal genome cell
18
Kay e al. 2025
19
Tobiasson e al. 2026 assume ha his p ocess was suppo ed by nume ous bu spo adic ho izon al acquisi ions
o genes om o he bac e ia bo h be o e and a e endosymbiosis.
20
Moody e al. 2024, Lambe 2024 In he LUCA publica ions, i is common p ac ice o use Giga (Ga) ins ead o
billions.
21
Kay e al. 2025, Figu e 1

Theo y_LUCA 6
( he i s one was called JCVI-syn1.0 o ‘Syn hia’ wi h 901 genes)
22
. Mycoplasma was he
smalles known au onomous cell ype and hus used as model o ganism since 1984. In 2016, a
new cell, called JCVI-syn3.0, was c ea ed by eplacing he genome o Mycoplasma cap icolum
wi h he genome o Mycoplasma mycoides
23
, wi h emo al o unessen ial deoxy ibonucleic acid
(DNA). I had only 473 genes, bu s ill he unc ion o 149 genes was unknown
24
. A e i was
ound ha a sligh ly la ge genome leads o imp o ed cell g ow h, a modi ied minimal cell was
c ea ed which allowed o educe he numbe o genes wi h unknown unc ion o 30 in he yea
2019
25
. In 2021, a e e se gene ics app oach de e mined ha se en genes a e equi ed oge he
o no mal cell di ision o he minimal cell and he addi ion o hese se en genes o he new
JCVI-syn3A esul ed in a no mal mo phology while JCVI-syn3.0 was pleomo phic wi h a low
eplica ion a e
26
.
A s udy om 2024 showed ha Mycoplasma mycoides and i s de i ed ‘minimal cell’ (JCVI-
Syn3A) could exis wi h a e y simple memb ane which consis ed o a wo-componen
lipidome
27
.
These esul s do no indica e ha he RNA wo ld hypo hesis is w ong, bu ha eplica ion wi h
DNA seems o equi e a ce ain complexi y and no clue o a simpli ied eplica ion in he
hypo he ical RNA wo ld could be ound.
Despi e he esea ch on a i icial and syn he ic cells, all modi ied and syn he ic o ganisms
including syn he ic i uses could only be p oduced in al eady li ing en i onmen s (only li e
can c ea e o he li e), i.e., he e is a clea bo de be ween dead and li ing ma e ials.
1.4 Findings in Ou e Space
In 2025, expe imen s on he In e na ional Space S a ion ISS showed ha A chaea, Fungi and
Bac e ia su i ed long- e m exposu e o open space. The expe imen named "Tes " showed ha
a e wo-yea s exposu e o open space, spo e- o ming bac e ia o he species Bacillus sub ilis,
ungi o he species Au eobasidium pullulans and a chaea o he species Me hanosa cina mazei
S-6T, deposi ed on co on wool, su i ed wi h dec eased numbe s
28
. The dehyd a ion and
pa ial lyophiliza ion in he space acuum may ha e con ibu ed o su i al
29
. E en he space
dus collec ed om he su ace o he ISS con ained biological objec s
30
. “Tes ” was he i s
long- e m ull exposu e o open space while o he expe imen s ("Exposu eE", "Exposu e-R",
"Bio isk", "Tanpopo") e alua ed only pa ial aspec s o space exposu e
31
. Also, inside he ISS.
The bac e ium E. bugandensis was ound which was di e en om e es ial a ian s and was
highly esis an agains an ibio ics by an ibio ic a ge al e a ion, an ibio ic e lux, educed
pe meabili y o an ibio ics, and an ibio ic inac i a ion
32
.
In addi ion, i was shown ha non-enzyma ic syn hesis o pep ides is possible in space
33
. A
s udy om 2025 ound bac e ia in ul a-s e ile spacec a -assembly NASA clean ooms despi e
22
Wang/Zhang 2019
23
Fu he e alua ions we e done wi h Mycoplasma pulmonis, Mycoplasma pnemoniae and Mycoplasma
geni alium, e e o Glass e al. 2017
24
Danchin/Fang 2016
25
Lachance e al. 2019
26
Pelle ie e al. 2021
27
Jus ice e al. 2024
28
Deshe aya e al. 2024
29
Deshe aya e al. 2024
30
Deshe aya e al. 2024
31
Deshe aya e al. 2024
32
Caldwell 2024, Sengup a e al. 2024
33
Baum 2026, Hopkinson e al. 2026
Theo y_LUCA 7
ex eme condi ions
34
; ano he s udy ha bac e ia and hei i uses and can adap hemsel es o
mic og a i y by co-e olu ion
35
.
These indings may indica e ha biomolecules e.g., om as e oids could ha e enabled and
accele a ed he ea ly phases o li e on he young ea h which was no p o ec ed by a hick
a mosphe e.
1.5 Po en ial Impac o A i icial In elligence
Howe e , he apid ad ances o A i icial In elligence (AI) in genome analysis and c ea ion o
na u al and a i icial p o eins as well as he abili y o analyze e y la ge genomic da a se s may
b ing a sudden b eak h ough in he LUCA deba e, bo h o he unde s anding o o igin o li e
as well as o he comple e syn hesis o li ing cells.
This could cause majo sa e y issues, as hese cells may cause in ec ions o con amina e
ecosys ems. The e is also a subs an ial isk o misuse.
Al eady exis ing AI-enabled biological ools we e meanwhile upda ed like he ad anced p o ein
s uc u e analyze AlphaFold-3 and he Cha GPT-like AI sys em E o2. AlphaFold 3 can p edic
he s uc u e o complexes including p o eins, nucleic acids, small molecules, ions, and
modi ied esidues.
36
Technologies like AlphaFold could be epu posed o enginee pa hogens
37
.
E o2 was ained on 9.3 illion DNA base pai s and wo ks wi h 40 billion pa ame e s o p edic
he unc ional impac s o gene ic a ia ions om noncoding pa hogenic mu a ions o clinically
signi ican gene a ian s. In addi ion, E o2 gene a es mi ochond ial, p oka yo ic, and
euka yo ic sequences a genome scale
38
. E o2 is a s ep owa ds designing comple ely new
genomes
39
.
2 Summa y
This wo king pape p o ided a b ie in oduc ion o he Las Uni e sal Common Ances o
LUCA and he po en ial biosa e y implica ions. LUCA is he hypo he ical p ecu so o all
mode n cells, i.e., he A chaea, he P oka yo es and Euka yo es (which a e he common ances o
o bac e ia, animals, ungi, and plan s). In his decade, he LUCA esea ch made subs an ial
p og ess by u ilizing apidly g owing genomic da abases and enhanced analysis me hods.
The gene ally accep ed heo y is ha li e s a ed wi h in e ac ions be ween ibonucleic acid
(RNA) and amino acids which o med complexes o eplica ion in a memb ane, i.e., a physical
bo de be ween cell and en i onmen . This is also known as ‘RNA wo ld’. la e ,
desoxy ibonucleic acid (DNA) was in eg a ed. Ea ly euka yo es in eg a ed euka yo es
alphap o eobac e ia in o a pe manen symbiosis (mi ochond ia in animals, chlo oplas s in
plan s) which enhanced me abolism and allowed he de elopmen o mul i-cellula o ganisms.
Howe e , in Decembe 2025, a calcula ion o mu a ion a es showed ha LUCA seemed o ha e
exis ed al eady sho ly a e he c ea ion o Ea h and Moon which was caused by he collision
o wo p o o-plane s 4.5 billion yea s ago. Some esea che s ound hin s ha LUCA was al eady
a qui e complex o ganism wi h an ea ly immune sys em agains i uses.
Bu as LUCA is he las cell, no he i s one, addi ional ime mus be added o he appea ance
o he i s uni e sal common ances o FUCA. Bu when adding his, he e is e y li le o no
ime le (dependen on he mu a ion a e calcula ion) since c ea ion o Ea h and Moon.
34
Amazouz 2025, Schul z e al. 2025
35
Huss e al. 2026
36
Ab amson e al. 2024
37
Haley/Bu ell 2025
38
B ixi e al. 2025
39
Callaway 2025
Theo y_LUCA 8
In 2025, expe imen s on he In e na ional Space S a ion ISS showed ha A chaea, Fungi and
Bac e ia su i ed long- e m exposu e o open space. E en he space dus collec ed om he
su ace o he ISS con ained biological objec s. In addi ion, i was shown ha non-enzyma ic
syn hesis o A chaea pep ides is possible in space. A s udy om 2025 ound bac e ia in ul a-
s e ile spacec a -assembly NASA clean ooms despi e ex eme condi ions; ano he s udy ha
bac e ia and hei i uses and can adap hemsel es o mic og a i y by co-e olu ion. These
indings may indica e ha biomolecules e.g., om as e oids could ha e enabled and accele a ed
he ea ly phases o li e on he young ea h which was no p o ec ed by a hick a mosphe e.
Expe imen s o c ea e syn he ic cells we e done wi h Mycoplasma mycoides which we e
enginee ed o minimal genome cells wi h he smalles possible genome ha allows au onomous
li e and eplica ion. These expe imen s showed ha eplica ion below a ce ain complexi y
almos comple ely s opped, i.e., no clues o a hypo he ical simpli ied cell eplica ion in an RNA
wo ld could be shown. Howe e , he apid ad ances o A i icial In elligence (AI) in genome
analysis and c ea ion o na u al and a i icial p o eins as well as he abili y o analyze e y la ge
genomic da a se s may b ing a sudden b eak h ough in he LUCA deba e, bo h o he
unde s anding o o igin o li e as well as o he comple e syn hesis o li ing cells which could
cause majo biosa e y issues ia in ec ion, con amina ion, o misuse.
3 Re e ences
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