Are tapeworms sticky?
2025/2/21
But Why: A Podcast for Curious Kids
C
Chelsea Wood
J
Jane Lindholm
@Jane Lindholm : 我最初认为寄生虫对宿主有害，它们以宿主的代价生存，有时甚至会致死。但通过与@Chelsea Wood 的对话，我了解到寄生虫在生态系统中扮演着重要的角色，它们有助于维持生态系统的平衡，防止任何一个物种数量过多。
Chelsea Wood: 我是一名寄生虫生态学家，我热爱寄生虫。寄生虫包括动物（如蠕虫、蜱虫、虱子）和非动物（如细菌、真菌、原生动物、病毒）。寄生是一种生存方式，寄生虫通过从宿主身上获取营养来生存。寄生虫的寿命差异很大，从几分钟到几十年不等。一些寄生虫的幼虫阶段寿命很短，只有几分钟到几小时的时间来寻找合适的宿主。绦虫不粘，而是滑溜的，它们很长是因为它们由许多节段组成，每个节段都是一个独立的生殖单位，可以脱落并繁殖。绦虫通常在脊椎动物的肠道中成熟，最初的宿主是鲨鱼。胃部对寄生虫来说是可利用的资源，因为自然界厌恶真空。寄生虫会对宿主产生负面影响，而共生生物则不会。我最初对寄生虫感到厌恶，但后来发现它们非常迷人，在显微镜下，它们非常美丽。鲨鱼绦虫完美地适应了鲨鱼肠道中的生活环境，它们利用触手上的倒刺来固定在鲨鱼肠壁上，抵抗粪便的冲刷。人体头虱只寄生在人类头上，它们以头皮上的死皮和血液为食，这会导致瘙痒。跳蚤和蚊子是远亲，它们独立进化出了吸血的习性。跳蚤更喜欢叮咬猫和狗，但也可能叮咬人。蜱虫和蚊子存在的原因与胃里的蠕虫一样，因为自然界厌恶真空。蜱虫的生命周期包括三个阶段，每个阶段都需要吸血。蜱虫可以通过叮咬传播莱姆病等疾病，蜱虫幼虫阶段从老鼠身上获得莱姆病细菌，然后在若虫阶段传播给人类。蜱虫叮咬有时会疼痛或刺痛，这是因为它们在叮咬过程中可能出现失误。我们不应该害怕寄生虫，因为它们在生态系统中扮演着重要的角色。寄生虫有助于维持生态系统的平衡，防止任何一个物种数量过多。寄生蜂等寄生虫对农业至关重要，它们可以控制害虫的数量。寄生虫是生命循环和生态系统的一部分，它们既不好也不坏。
supporting_evidences
Chelsea Wood: 'I'm Chelsea Wood. I'm an associate professor...because parasites are my favorite things.'
Chelsea Wood: 'Our definition of parasite encompasses parasites that are animals like worms, ticks, lice, but also things that aren't animals like bacteria, fungi, protozoa, viruses.'
Chelsea Wood: 'Tapeworms are really interesting because while they look like an unspooled strip of tape, they're actually made up of tens, sometimes hundreds, of individual segments...'
Chelsea Wood: 'Ticks actually have a totally fascinating life cycle, usually involving three different stages...'
Chelsea Wood: 'Many kids know that some ticks can make people sick. One of the diseases you can get from a tick is called Lyme disease...'
Chelsea Wood: 'A lot of our food, our crops, rely on parasites like aphid-killing wasps...'
Deep Dive
This chapter defines parasites, highlighting their negative impact on hosts but emphasizing their crucial role in maintaining healthy ecosystems. It introduces parasite ecologist Chelsea Wood and explores the diverse types of parasites, including those found in humans and wildlife.
- Parasites are organisms that live in or on other organisms and cause harm.
- Parasites play a vital role in maintaining the balance of ecosystems.
- Different types of parasitic relationships exist: parasites, mutualists, and commensals.