Who are the engineers NOT mentioned in the passage?

Read the given passage and answer the question that follows.

Earth Day is an apt moment to consider how our planet, a majestic 4.54 billion years old, is faring. The statistics are not pleasing. Once covered in verdant green, FAO finds Earth has now lost one-third of its forests through human activity. WWF estimates such land-use changes have caused wildlife to decline by 69% in the last 50 years. The loss of natural ecosystems and their engineers, which includes birds, animals, insects and fungi, is literally drying up the world. The UN finds 75% of Earth’s land is degraded while its oceans are 30% more acidic now, choked by plastic and chemical waste. Neither is the air pristine – as pollutants coat the skies, the World Economic Forum finds global CO2 emissions rose in 2022 to a record high. Such CO2 covers Earth in a sheath which doesn’t let it release heat into space, trapping this in the atmosphere instead, making Earth 1.11 degrees warmer.