You'll see why I didn't spell out "AGD" when you look at the paper :)

While watching the Netflix documentary about plastics and fertility ("The Plastic Detox"), they had a shot of Dr. Swan's paper. The voiceover talked about how strong the relationship was between AGD and semen concentration.

Problem was that the scatter plot looked to me like there was hardly any relationship between those two variables.

So I went and looked at the paper (better format) and, while the R squared values for the plots in Figure 3 weren't given, it looked really low. Table 3 above claims a very low p value for the AGD and semen concentration.

image of plot and table

So the authors are claiming a relationship there and I'm not really understanding why the relationship doesn't show up in the scatter plot and why their beta coefficient and low p value does indicate a relationship.

Not well versed in statistics, so please ELI5.