\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage[round]{natbib}
\let\cite\citep




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[greek,english]{babel}










\begin{document}

\title{Chemical biomarker robustness in Martian planetary analogue evaporite
mineralogy}



\author[1]{Scott M. Perl}%
\author[2]{Aaron J. Celestian}%
\author[3]{Bonnie M. Baxter}%
\author[4]{Preston Tasoff}%
\affil[1]{California Institute of Technology, NASA Jet Propulsion Laboratory}%
\affil[2]{Natural History Museum of Los Angeles County (NHM)}%
\affil[3]{Great Salt Lake Institute, Westminister College}%
\affil[4]{Department of Biology, Washington University in St. Louis}%


\vspace{-1em}



  
  \date{May 19, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup








\sloppy


\section*{Introduction \& Motivation}

{\label{249472}}

Indications of extant or extinct life in the Martian shallow subsurface
can be preserved alongside the evaporitic mineral record within sites
where dried ancient lake systems~are observed. Biological chemical
markers (biomarkers) lose molecular stability over time, and detections
of these over geologic time present challenges to biogenic validation.

~

Agnostic biomarkers and the preservation of those in-situ molecules can
be aided by biological feedback to ecological stresses that have been
interpreted throughout the late Noachian/early
Hesperian~\cite{Ehlmann_2014,Murchie_2009}. Global desiccation and surface wide UV
exposure are the major obstacles to in-situ biological preservation in
the shallow crust \cite{Cockell_2000}. Burial of sedimentary material
from early Hesperian aqueous sites can provide significant protection
from these damaging effects.~

\par\null

The purpose of this paper is to discuss the biological feedback from
microbial communities preserved within Martian analogue mineralogy.
Furthermore, we explore how biosignature preservation pathways can
outlast the original biology in slow-changing evaporite mineral
records.~

\par\null

\section*{Geobiological Preservation \&
Terrestrial}

{\label{791633}}

Biological Adaptation: Our continued focus is evaporating and dried
terrestrial lake beds~\cite{Baxter_2018} since that has proven to be
ideal for modern and older biogenic preservation (\emph{Perl in prep.
2019}). Mineral-microbe interactions can produce nutrients and sustained
\selectlanguage{greek}μ\selectlanguage{english}m-scale environments where nutrient cycling and metabolic processes
continue to produce useful proteins that combat ecological stresses
found in measured OTUs from amplification of 16S rRNA
(Figure~{\ref{461273}}). Stated differently, molecular
adaptations from surviving bacteria allow for later generations to
better utilize their environments thereby showing significant
similarities between ancient and younger prokaryotes~\cite{Maughan_2002}.
On Earth these similarities can yield to difficulty between relative age
dating of bacteria and ruling out ``modern'' contamination of older
mineral samples. Sedimentological relative dating of minerals can
greatly assist with regard to preservation of biological material.
However continued metabolic processes in preserved settings will lead to
taxa differences (via neighbor joining clustering~\cite{Saitou1987}
when compared to the non-preserved environment. Hence, the need for
proper~ baseline environmental controls and understanding of
contamination either from younger fluids or rock and mineral fracture.~

\par\null

\subsection*{Early Peptide Chains}

{\label{175066}}

If an independent origin of life on Mars and accompanying evolution
pathways existed, the earliest evolved simple polypeptides may not have
had the capacity for adaptation in the timeframe of climate change on
Mars. Biochemically though, the very existence of these polypeptides may
have been enough to provide feedback to ecological stresses. The
timelines of C,H,O,N,P,S, a solvent (water), and environmental
conditions overlapping would be the indicator of the duration of
habitability. This duration would parallel the adaptability of organisms
and the synthesis of more complex peptide chains leading to a greater
ability to adapt to the changing Martian surface over geologic time.~

\par\null\par\null\selectlanguage{english}
\begin{figure}[h!]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/LPSC-2019-figure-1/LPSC-2019-figure-1}
\caption{{Operational Taxonomic Units preserved in halite evaporite minerals
showing community preference directly associated with protein production
associated with ecological feedback to stressful environments.
{\label{461273}}%
}}
\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\bibliographystyle{plainnat}
\bibliography{bibliography/converted_to_latex.bib%
}

\end{document}

