In biology class, when talking about plants, going over how fruit trees make fruit sweet to attract animals to eat it so it spreads it's seeds, etc. There is some type of intelligence in that.
Your statement is also what is called an argument from ignorance or an argument from incredulity. Essentially you're saying that since you cannot comprehend how such a seamless symbiotic relationship between plants and animals can come about naturally without some intelligent intervention, then there really must be some intelligence behind it. But the mistake being made here is in assuming (subconsciously) that anything you cannot explain or comprehend naturally, must therefore not have a natural explanation.
You are assuming, subconsciously, that the natural reality around you must be limited by your own ability to comprehend it and therefore if you can't comprehend it then it must not be natural. This is a common flaw in reasoning engaged in by humans. This type of reasoning is also seen in newly contacted peoples who have lived in isolated forested regions for thousands of years and are encountering modern technology for the first time. Because of being completely ignorant of the laws of physics behind modern technology they are unable to comprehend how such modern technologies as cell phones or cameras work and so they resort to reasoning that it must be magic and the people who wield them must be gods. Because you do not know and cannot comprehend how life originated naturally without intelligence does not mean it did not originate without intelligence - it only means that you do not know how it originated without intelligent.
Always remember: natural reality is not limited by your ability to comprehend it naturally so that you should label that which you cannot naturally comprehend as being supernatural. If you do so, you'd be making the same mistake as those "primitive" peoples who, in their ignorance and inability to comprehend, label modern technology as magic.