Final answer:
Leeches are either predators or parasites that use a proboscis to feed, and while not major vectors for human diseases like mosquitoes, they have complex biological characteristics that impact ecosystems and can be studied to better understand their roles.
Step-by-step explanation:
The subject in question pertains to leeches, which are parasitic or predatory creatures that can either feed off the blood of vertebrates or capture and eat other invertebrates. Leeches utilize a tubular organ called a proboscis for feeding. When examining their role in ecosystems and their interaction with humans, it's important to note that like mosquitoes and ticks, leeches can be vectors for disease, although they are not typically associated with the spread of human diseases as mosquitoes are. In the context of human health, diseases such as malaria have a significant impact, transmitted by mosquitoes through parasitic infestations of the blood.
Insects, including flies, ticks, fleas, and lice, can be vectors for various diseases that affect human populations. The referenced video by Science Friday sheds light on some of the more interesting properties of leeches, which, despite their often negative reputation, have fascinating biological characteristics. A better understanding of leeches and other insects can provide insights into their roles in ecosystems and inform public health strategies.