A few months ago I pondered HD 60584 CC1 and HIP 21152. These are F stars ~1.4 M⊙, so aren't likely to have planets with Cambrian-plus life on them, unless some alien terraforms it all. They also each own a browndwarf in the low 30s Mj over 16 AU out.
It was my thought that, if they did have an Earth-mass planet at 2 AU (the habitable zone), the eccentricity would be a problem even for Ediacaran life.
Per Jules Bernstein, eccentricity might be good. Pam Vervoort et al. poses the constraint of a closer and eccentric Jupiter. Right now, Jupiter pulls Mars into an eccentric orbit but not (so much) Earth. A closer Jupiter is presumed to have yeeted Mars away so it's now looking to the next planet inward: Earth. The eccentricity pushes irradiance on summers more than winters. Warmer summers mean better crops.
There's no "global warming" on account Jupiter hasn't changed our temperature overall. For the winters - which will be longer given Kepler - we suppose everyone just hunkers down.
Anyway I expect the Earth would, actually, get more eccentric as time goes on if only because it can hardly get less so. Maybe a big rock might help us along. I however doubt any influence from Jupiter; the giant is not as vulnerable as is, say, Neptune. So by the time we get to enjoy the extreme-r seasons, the hotter Sun has already done for us.
Hence my interest not in this system but in others', like HD 60584 CC1 and HIP 21152.
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