Spider-like creatures help us understand fatherhood

Topic: Biology

Citizen scientists and researchers studied harvestmen, a group of spider-like arachnids. They found that parental care evolved multiple times in these creatures, and it's not just the females who take care of their young.

Harvestmen are small, eight-legged creatures that look like spiders but belong to a different group called arachnids. Researchers led by Glauco Machado from the University of São Paulo wanted to understand how parental care evolved in these creatures.

They combined data from nearly 30 years of field research with observations submitted through the iNaturalist platform, which is used by citizen scientists around the world. This helped them more than double the number of documented examples of parental care in harvestmen.

The researchers found that maternal care (when females take care of their young) evolved only from species that showed no parental care before. But paternal care (when males take care of their young) followed two different paths: it either emerged directly from species with no parental care or from species where females already guarded the eggs.

This suggests that different evolutionary pressures shaped the development of maternal and paternal care in harvestmen. The researchers also found that when paternal care evolved from maternal care, it likely reflects a form of sexual selection known as 'enhanced fecundity', where females prefer males who are already caring for eggs.

Why It Matters

Understanding how parental care evolved in harvestmen can help us better understand the evolution of parenting in other animals. It also shows the power of citizen science in accelerating research and providing valuable data to scientists.

Key Facts

• Harvestmen are a group of spider-like arachnids with over 6900 identified species.
• The researchers combined field data with iNaturalist observations to study parental care in harvestmen.
• Maternal care evolved only from species that showed no parental care before.
• Paternal care followed two different paths: it either emerged directly or from species where females already guarded the eggs.
• The study used citizen science data to more than double the number of documented examples of parental care in harvestmen.

Key Terms

Maternal care

When a female takes care of her young

Paternal care

When a male takes care of his young

Implications

Understanding how parental care evolved in harvestmen can help us better understand the evolution of parenting in other animals. It also shows the power of citizen science in accelerating research and providing valuable data to scientists.