As African wildlife continues to evolve under environmental pressures, a genetic study has shed light on how indigenous African suids—such as the common warthog and the red river hog—have adapted to their unique habitats.
The research, Dr. Adeniyi Charles Adeola of the Kunming Institute of Zoology, Chinese Academy of Sciences was one of the leading authors, in collaboration with African institutions, reveals critical genetic adaptations that help these animals thrive in diverse ecosystems.
Speaking on the study, Dr. Adeola emphasized its significance in understanding Africa’s rich biodiversity. “Unlike Eurasian wild boars, which exist as a single species across the continent, African suids display remarkable diversity, each species uniquely adapted to its environment. Our study explores the genetic basis of these adaptations, providing insights that could benefit conservation efforts and even livestock breeding,” he explained.
The researchers sequenced the genomes of a female red river hog and a male common warthog from Nigeria’s Gashaka-Gumti National Park. Additional samples were collected from a male red river hog in Cross River National Park and nine common warthogs from Kenya’s central highlands. The team utilized cutting-edge long-read sequencing technologies, including Oxford Nanopore PromethION and PacBio Sequel, alongside Illumina NovaSeq 6000 for paired-end re-sequencing.
One of the major findings of the study was the evolutionary trajectory of these species. By reconstructing their demographic histories using a pairwise sequential Markovian coalescent (PSMC) model, the researchers found that the common warthog has maintained a larger population size over time compared to the red river hog. “This is likely due to its broader habitat range, allowing for greater adaptability across different African landscapes,” Dr. Adeola pointed out.
The study also revealed intriguing genetic adaptations, particularly in sensory perception. “We discovered that the common warthog has undergone strong selective pressure in genes related to vision, olfaction, and auditory functions,” Dr. Adeola noted. “This suggests that heightened sensory perception plays a crucial role in their survival, helping them detect predators and navigate complex environments.”
In particular, 19 regulatory and positively selected genes (REGs and PSGs) were found to be associated with retina development, photoreceptor maintenance, and overall eye health in the warthog. These included genes responsible for retina function, such as ALB, NRCAM, and TGIF2, as well as those essential for photoreceptor maintenance, including GPR179 and GRK1. “This level of genetic refinement in vision is fascinating and underscores the importance of sight in warthog behaviour and survival,” Dr. Adeola added.
Conversely, the red river hog showed significant genetic adaptations related to immune response, metabolism, and nervous system development. “Our analysis identified several genes linked to viral resistance, suggesting that red river hogs may have evolved mechanisms to combat infectious diseases more effectively,” Dr. Adeola stated. “This could have implications for understanding disease resistance in wild and domestic pigs alike.”
The research also drew comparisons between African suids and their Eurasian counterparts, such as the European wild boar and the southern East Asian wild boar. Interestingly, while the population size of the common warthog and the European wild boar showed a minor peak shortly after the Last Glacial Maximum (LGM), the red river hog did not experience the same trend. “This tells us that environmental events, such as climate shifts, have played a role in shaping the genetic diversity of these species differently,” Dr. Adeola explained.
Despite the success of the study, Dr. Adeola acknowledged the challenges in conducting such large-scale genomic research. “One of the biggest hurdles we faced was obtaining high-quality DNA samples from wild animals in remote locations. Field collection requires careful planning and collaboration with local conservation authorities,” he noted.
“Additionally, sequencing and assembling large genomes demand significant computational resources, which can be a bottleneck in some African research institutions.”
The study’s findings have important implications beyond evolutionary biology. Dr. Adeola highlighted potential applications in conservation and livestock breeding. “Understanding the genetic adaptations of these species could help in designing conservation strategies to protect their populations. It could also contribute to breeding programs aimed at improving disease resistance and environmental adaptability in domestic pigs,” he said.
The research is also an example of successful international collaboration between China and Africa in the field of genetics. “This study was made possible through partnerships with institutions such as the International Livestock Research Institute (ILRI) and the Kenya Wildlife Service (KWS). Strengthening scientific collaboration between Africa and China is key to unlocking more discoveries that can benefit both wildlife and agriculture,” Dr. Adeola emphasized.
Looking ahead, the research team plans to expand their work by sequencing additional suid species across Africa to further explore their evolutionary history and adaptations. “We are only beginning to scratch the surface of the genetic diversity within African wildlife. Future studies will help us better understand how these animals have evolved and what genetic traits contribute to their survival,” Dr. Adeola concluded.
