In memory of Professor Tang Yan-Cheng, whose work bridged traditional knowledge and cutting-edge evolutionary science.
Explore the ScienceNot so long ago, evolutionary biology primarily meant studying fossilized bones and comparing skeletal structures. Today, this vibrant field has transformed into an interdisciplinary science where ancient DNA reveals lost worlds, CRISPR gene editing recreates evolutionary adaptations, and AI algorithms predict how species might respond to climate change. The framework first established by Darwin and Wallace now integrates advanced technologies that let us read life's history with unprecedented clarity while addressing urgent challenges in medicine, conservation, and climate change 8 .
The field has expanded from historical analysis to predictive science, allowing researchers to not just reconstruct life's past but to forecast its future trajectories. In this article, we explore how systematic and evolutionary biology is being reimagined through cutting-edge research, celebrating the legacy of Professor Tang Yan-Cheng, whose work helped bridge traditional biological knowledge with modern evolutionary theory.
Modern evolutionary biology integrates multiple disciplines to understand life's complexity
At the heart of evolutionary biology lies phylogenetics—the science of reconstructing evolutionary relationships. Think of it as creating a comprehensive family tree for all life forms, but one based on DNA sequences rather than family stories 8 .
While natural selection remains a cornerstone, evolutionary biologists now recognize additional powerful mechanisms:
By comparing DNA sequences between species and counting genetic differences, scientists can estimate when species diverged using "molecular clocks." This approach complements fossil evidence and often provides dates for evolutionary splits where no fossil record exists 4 .
The ability to extract and sequence genetic material from long-dead organisms has revolutionized evolutionary biology. In 2025, scientists announced the recovery of microbial DNA from mammoth remains dating back over one million years—the oldest host-associated microbial DNA ever recovered 4 .
Similarly, analysis of ancient human DNA continues to rewrite our own story. Recent findings revealed that a mysterious gene called MUC19, inherited from Denisovans, may have helped modern humans adapt to cold environments 4 .
The COVID-19 pandemic made viral evolution a household topic, but evolutionary principles are now applied far beyond virology. Cancer researchers have adopted evolutionary models to understand how tumor cells evolve resistance to chemotherapy 8 .
The antibiotic resistance crisis represents another frontline where evolutionary biology provides crucial insights. Researchers are testing innovative solutions including multidrug approaches and the use of bacteriophages to delay the evolution of resistance in pathogenic bacteria 8 .
The gene-editing technology CRISPR has become more than a tool for genetic engineering—it has emerged as a powerful instrument for evolutionary experimentation. Scientists can now resurrect extinct genetic variants or introduce specific mutations into model organisms to test how historical genetic changes contributed to evolutionary adaptations 2 .
This approach has shed light on everything from how ancient fish evolved teeth to what genetic changes enabled early humans to develop larger brains. CRISPR-based therapies have now entered clinical practice, with the first FDA-approved treatment for sickle cell disease representing a landmark in applying our evolutionary knowledge 5 .
Unraveling the Bed Bug's Renaissance
As cities grew denser and global travel expanded, bed bugs staged a remarkable comeback. Evolutionary biologists recognized this phenomenon as a perfect natural experiment: how do insects adapt when suddenly confronted with widespread insecticide use and new urban environments? A 2025 study set out to answer this question by comparing the whole genome sequences of two genetically distinct lineages of bed bugs 4 .
Researchers collected bed bug specimens from diverse urban environments across multiple cities, ensuring genetic diversity in their sample.
High-quality DNA was carefully isolated from tissue samples, preserving long strands for comprehensive sequencing.
Using next-generation sequencing technology, the team determined the complete DNA sequence of each specimen, generating billions of data points.
Sophisticated algorithms identified genetic differences between populations, focusing on mutations that might confer insecticide resistance.
Researchers scanned genomes for patterns indicating "selective sweeps"—where beneficial mutations become widespread in a population through natural selection.
Candidate genes were inserted into model insects using CRISPR technology to verify their role in insecticide resistance 2 .
Computer simulations reconstructed the spread of resistance mutations through urban bed bug populations 7 .
The study yielded remarkable insights into the rapid evolution of urban pests. Genetic analysis revealed that bed bugs may be "the first true urban adapters," having evolved specifically for human-built environments 4 .
| Gene Name | Mutation Type | Resistance Mechanism | Insecticides Affected |
|---|---|---|---|
| CYP397A1 | Overexpression | Enhanced detoxification | Pyrethroids, Neonicotinoids |
| VGSC | Point mutation | Target site insensitivity | Pyrethroids, DDT |
| GST | Gene duplication | Metabolic resistance | Organophosphates |
| AChE | Structural change | Enzyme modification | Carbamates |
| Time Period | Dominant Resistance |
|---|---|
| Pre-1950 | None documented |
| 1950s-1980s | Target site mutations (VGSC) |
| 1990s-2000s | Metabolic resistance (GST) |
| 2010s-Present | Multiple mechanisms combined |
Perhaps most surprisingly, the researchers discovered that resistant bed bugs carried mutations not present in their rural counterparts just decades earlier, demonstrating evolutionary change occurring within human timescales. The speed of this adaptation was facilitated by the short generation time of bed bugs and the intense selection pressure imposed by insecticide application.
Modern evolutionary biology relies on sophisticated tools and techniques
DNA/RNA sequencing for comparing whole genomes across species and identifying genetic variation.
Gene editing for testing function of evolutionary mutations and recreating ancestral variants.
DNA amplification for copying ancient DNA fragments and preparing sequencing libraries.
DNA cutting for analyzing genetic variation and preparing samples for sequencing.
Molecular labeling for tracking gene expression patterns in developing embryos.
Data analysis for reconstructing evolutionary trees and detecting natural selection.
| Tool/Reagent | Primary Function | Application in Evolutionary Research |
|---|---|---|
| Next-Generation Sequencers | DNA/RNA sequencing | Comparing whole genomes across species; identifying genetic variation |
| CRISPR-Cas9 Systems | Gene editing | Testing function of evolutionary mutations; recreating ancestral variants |
| DNA Polymerases | DNA amplification | Copying ancient DNA fragments; preparing sequencing libraries |
| Restriction Enzymes | DNA cutting | Analyzing genetic variation; preparing samples for sequencing |
| Fluorescent Tags | Molecular labeling | Tracking gene expression patterns in developing embryos |
| Bioinformatics Pipelines | Data analysis | Reconstructing evolutionary trees; detecting natural selection |
As we stand at the intersection of genomics, computational biology, and biotechnology, evolutionary biology has never been more vibrant or relevant. The field continues to unravel life's greatest mysteries while providing crucial insights for addressing practical challenges from antibiotic resistance to climate change adaptation. The integration of artificial intelligence and machine learning promises to further accelerate discoveries, helping researchers identify patterns in massive datasets that would be impossible to discern manually 2 .
The emerging biotechnology landscape—with its growing capabilities to read, write, and edit genetic code—will continue to transform evolutionary research while raising important ethical questions that society must grapple with 5 . As these technologies advance, the principles of evolutionary biology will become increasingly important for guiding their responsible development and application.
Their dedication to understanding life's complexity continues to inspire new generations of researchers who will carry forward the mission to unravel evolution's secrets and apply this knowledge for the benefit of humanity and our planet.