Researchers have found a high diversity of Darwin wasps in a tropical rainforest in Brazil, contradicting the long-held belief that these wasps prefer cooler habitats.

The wasps, named after Charles Darwin who first described them, are parasitoids that use other insects and spiders as hosts for their offspring.

The researchers discovered 98 species of Darwin wasps on a mountain in the Brazilian Atlantic Rainforest, a biodiversity hotspot that is threatened by deforestation and climate change.

What are Darwin wasps and why are they important?
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Darwin wasps are a group of insects that belong to the family Ichneumonidae, which contains about 25,000 species worldwide.

They are also known as ichneumon wasps or parasitoid wasps, because they lay their eggs inside or on the bodies of other arthropods, such as caterpillars, beetles, flies, and spiders.

The wasp larvae then feed on the host's tissues until they are ready to emerge as adults, often killing the host in the process.

Darwin wasps are important for the ecological balance of ecosystems, as they regulate the populations of their hosts and prevent them from becoming pests.

They are also indicators of environmental health, as they are sensitive to habitat changes and pollution.

Moreover, they are a source of biological and evolutionary information, as they exhibit a remarkable diversity of forms, behaviors, and adaptations.

How did the researchers find and identify the Darwin wasps?

The researchers, from the University of York in the UK and the Federal University of São Carlos in Brazil, conducted a survey of Darwin wasps on a mountain in the Serra do Mar State Park, a protected area of the Brazilian Atlantic Rainforest.

They used different types of traps to collect the wasps at three altitudes: low (200 m), mid (800 m), and high (1400 m).

They also sampled the wasps during two seasons: dry (June to August) and wet (December to February).

The researchers used morphological and molecular methods to identify the wasps, comparing them with existing records and descriptions.

They found that the wasps were more diverse and abundant at the low and mid altitudes than at the high altitudes and that there was no significant difference between the dry and wet seasons.

They also found that 75% of the wasps could not be assigned to any known species, suggesting that they were new to science.

The researchers estimated that there were 98 species of Darwin wasps on the mountain, similar to the number of species found in the whole of the UK.

They also calculated that the mountain could host up to 200 species of Darwin wasps, based on the extrapolation of the observed diversity patterns.

Also Read: New Cuckoo Wasp in Northern Europe: New DNA Readings

What are the implications and challenges of the study?

The study, which was published in the journal Insect Conservation and Diversity, challenges the assumption that Darwin wasps are not suited for the tropics and shows that they are more diverse and widespread than previously thought.

The study also highlights the importance of the Brazilian Atlantic Rainforest as a hotspot of biodiversity and the need to protect and restore it from the threats of deforestation and climate change.

The researchers acknowledged that there are some limitations and challenges in their study, such as the difficulty of identifying the wasps, the lack of knowledge about their biology and ecology, and the potential impact of human activities on their populations.

They called for more research and collaboration to explore the diversity and distribution of Darwin wasps in the tropics and to understand their role and function in the ecosystems.

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