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Biology

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Origin of life

Before there were cells, there were molecules. How did chemical systems begin passing useful abilities to descendants and sustaining their own reproduction?

Biological aging

Cells change, tissues lose resilience and organs age at different rates. Which changes drive the others, and how do they become a whole-body process?

Eukaryogenesis

Complex cells with nuclei descended from simpler ancestors. How did their internal compartments, mitochondria, and distinctive cellular organization come together?

Evolution of multicellularity

Cells have repeatedly evolved into organisms that live and reproduce together. What turns a group of cells into a coherent evolutionary individual?

Sex chromosome evolution

Some lineages keep the same sex chromosomes for vast spans of time; others replace them repeatedly. Why do their evolutionary paths differ so much?

Latitudinal diversity gradient

Many groups contain more species near the equator than near the poles. Which ecological and evolutionary processes generate this large-scale pattern?

Species coexistence

Many species persist together despite competing for resources. Which mechanisms keep any one competitor from excluding the others in real, changing ecosystems?

Gene regulatory grammar

Cells with similar DNA can activate very different genes. How do regulatory sequences and cellular conditions specify when, where, and how strongly a gene is used?

Developmental robustness

Developing organisms often produce reliable structures despite molecular noise, genetic differences, and environmental changes. How is that reliability achieved?

Regeneration

Some animals rebuild lost body parts, while others mostly form scars. What determines whether damaged tissue can reconstruct an organized, functional structure?

Alzheimer’s disease

Amyloid, tau, immune activity, and other changes accompany Alzheimer’s disease. How do they interact to cause neuronal dysfunction, and why does the course differ between people?

Parkinson’s disease

Parkinson’s disease affects multiple cells and systems, yet people develop it through different combinations of risks. What drives the damaging processes and their spread?

Long COVID

Some people experience persistent or new health problems after SARS-CoV-2 infection. Which biological processes sustain these different conditions?

Tumor dormancy

Cancer cells can persist quietly for years and later form a new tumor. What keeps them dormant, and what allows them to start growing again?

Antibiotic persistence

Some bacteria survive an antibiotic exposure without inheriting resistance to the drug. What allows these persister cells to survive and later resume growth?

Human microbiome causality

Microbial communities differ between people and are associated with many health conditions. Which differences change the host, and which simply reflect other changes?

Animal magnetoreception

Many animals use Earth’s magnetic field to orient themselves. How does that weak field become a signal their nervous systems can use?

Origin of the genetic code

Cells translate genetic sequences into proteins. How did a code and the machinery that reads it arise together?

Origin of viruses

Viruses have remarkably different genomes and structures. Did their major lineages emerge independently, and from what ancestors?

Flowering plant origins

Fossils and DNA offer different timelines for the earliest living flowering-plant lineages. Why do their estimated beginnings still disagree?

Biological homochirality

Life predominantly builds proteins and nucleic acids from particular mirror-image forms. How did those molecular preferences become established?

Circadian temperature compensation

Most chemical reactions change speed with temperature. A plant’s daily clock can keep nearly the same rhythm. How do its components cooperate to do that?