Scientists have recently discovered what could be the largest and oldest living organism on Earth, a giant fungus that is an interwoven filigree of mushrooms and rootlike tentacles spawned by a single fertilized spore some 10,000 years ago and extending for more than 30 acres in the soil of a Michigan forest.

为什么不能用extends?

and 为什么不能引导两个完整句？都修饰 a giant fungus, 整句就是：a giant fungus that is...and extends? 是不是这个extending修饰rootlike tentacles? 那也不应该加and啊？

谢过！！

为什么不能用extends?

注意这个句子的结构：a giant fungus that is an interwoven filigree of mushrooms and rootlike tentacles （spawned ）by a single fertilized spore some 10,000 years ago and （extending） for more than 30 acres in the soil of a Michigan forest.

spawned 和extending在这里都是分词，没有充当谓语