Bird species extinctions are far more impactful than we realized

Over the past 130,000 years, human activities have led to the extinction of hundreds of bird species, according to Earth.com. This has resulted in substantial reductions in avian functional diversity – the range of different roles and functions that birds perform in the environment.

While humans have been contributing to the global loss of species diversity for thousands of years, the impacts on other dimensions of biodiversity are not yet clear.

New research led by the University of Birmingham highlights the severe implications of the ongoing biodiversity crisis and emphasizes the urgent need to identify the ecological functions being lost through extinction.

From the well-documented demise of the Dodo to the recent extinction of the Kaua?i ?o?o songbird declared in 2023, scientists have evidence of at least 600 bird species having become extinct due to human activities since the Late Pleistocene, when modern humans began spreading across the world.

Utilizing the most comprehensive dataset to date of al
l known bird extinctions during the Late Pleistocene and Holocene, the study examines the broader implications of these losses on the planet.

‘Humans have been driving a global erosion of species richness for millennia, but the consequences of past extinctions for other dimensions of biodiversity – functional and phylogenetic diversity – are poorly understood,’ wrote the study authors.

‘In this work, we show that, since the Late Pleistocene, the extinction of 610 bird species has caused a disproportionate loss of the global avian functional space along with more than 3 billion years of unique evolutionary history.’

Study lead author Tom Matthews is an expert in global environmental change at the University of Birmingham.

Matthews noted that while the sheer number of bird species lost is a big part of the extinction crisis, what we also need to focus on is that every species has a job or function within the environment and therefore plays a really important role in its ecosystem.

The researchers found tha
t the extent of human-induced bird extinctions to date has resulted in the loss of approximately three billion years of unique evolutionary history and a 7% reduction in global avian functional diversity.

This is a significantly larger amount than expected based on the number of extinctions alone.

Given the wide range of crucial ecological roles performed by birds, the loss of avian functional diversity likely has far-reaching implications.

These post-extinction aftershocks include reduced flower pollination, diminished seed dispersal, the breakdown of natural control over insect populations – including many pests and disease carriers – and increased disease outbreaks due to decreased consumption of carrion.

Moreover, the reduction in global bird populations documented in the research may affect the ability of many plant species to adapt to current and future climate change.

The study is published in the journal Science.

Source: Azerbaijan State News Agency